{"id":"CVE-2025-15661","aliases":["ALPINE-CVE-2025-15661","AZL-90936","BELL-CVE-2025-15661","CLSA-2026-1791823540","DEBIAN-CVE-2025-15661","EUVD-2025-210285","GHSA-3wqh-87fg-ffgg","JLSEC-2026-659","MGASA-2026-0273","OESA-2026-3014","OESA-2026-3015","OESA-2026-3016","OESA-2026-3017","OESA-2026-3479","RHSA-2026:30132","ROOT-OS-DEBIAN-12-CVE-2025-15661","SUSE-SU-2026:23049-1","SUSE-SU-2026:23187-1","SUSE-SU-2026:23214-1","SUSE-SU-2026:23225-1","SUSE-SU-2026:23245-1","SUSE-SU-2026:3525-1","SUSE-SU-2026:3526-1","SUSE-SU-2026:3541-1","SUSE-SU-2026:4095-1","UBUNTU-CVE-2025-15661","USN-8486-1","openSUSE-SU-2026:11109-1","openSUSE-SU-2026:21549-1"],"status":"published","title":"libssh2 - Heap Buffer Over-read via sftp_symlink() in sftp.c","description":"libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.","severity":{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00648,"percentile":0.51568,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-125"],"published":"2026-06-18T20:18:29Z","modified":"2026-11-12T07:06:28Z","fixes":[{"ecosystem":"Alpine:v3.24","package":"chromium-rust","fixed_in":["1.96.1-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.21","package":"libssh2","fixed_in":["1.11.1-r3"],"sources":["osv"]},{"ecosystem":"Alpine:v3.22","package":"libssh2","fixed_in":["1.11.1-r3"],"sources":["osv"]},{"ecosystem":"Alpine:v3.23","package":"libssh2","fixed_in":["1.11.1-r4"],"sources":["osv"]},{"ecosystem":"Alpine:v3.24","package":"libssh2","fixed_in":["1.11.1-r4"],"sources":["osv"]},{"ecosystem":"Alpine:v3.24","package":"rust","fixed_in":["1.96.1-r0"],"sources":["osv"]},{"ecosystem":"Azure Linux:3","package":"libssh2","fixed_in":["1.11.1-4"],"sources":["osv"]},{"ecosystem":"Alpaquita:23","package":"libssh2","fixed_in":["1.11.1-r2"],"sources":["osv"]},{"ecosystem":"Alpaquita:25","package":"libssh2","fixed_in":["1.11.1-r3"],"sources":["osv"]},{"ecosystem":"Alpaquita:stream","package":"libssh2","fixed_in":["1.11.1-r4"],"sources":["osv"]},{"ecosystem":"Alpaquita:stream","package":"rust","fixed_in":["1.96.1-r0"],"sources":["osv"]},{"ecosystem":"Debian:12","package":"libssh2","fixed_in":["1.10.0-3+deb12u1"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"libssh2","fixed_in":["1.11.1-1+deb13u1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"libssh2","fixed_in":["1.11.1-4"],"sources":["osv"]},{"ecosystem":"Julia","package":"LibSSH2_jll","fixed_in":["1.11.102+0"],"sources":["osv"]},{"ecosystem":"openEuler:20.03-LTS-SP4","package":"libssh2","fixed_in":["1.9.0-12.oe2003sp4"],"sources":["osv"]},{"ecosystem":"Red Hat:hummingbird:1","package":"libssh2","fixed_in":["0:1.11.1-9.hum1"],"sources":["osv"]},{"ecosystem":"Red Hat:hummingbird:1","package":"libssh2-devel","fixed_in":["0:1.11.1-9.hum1"],"sources":["osv"]},{"ecosystem":"Red Hat:hummingbird:1","package":"libssh2-docs","fixed_in":["0:1.11.1-9.hum1"],"sources":["osv"]},{"ecosystem":"Ubuntu:24.04:LTS","package":"libssh2","fixed_in":["1.11.0-4.1ubuntu0.24.04.2"],"sources":["osv"]},{"ecosystem":"Ubuntu:25.10","package":"libssh2","fixed_in":["1.11.1-1ubuntu0.25.10.2"],"sources":["osv"]},{"ecosystem":"Ubuntu:26.04:LTS","package":"libssh2","fixed_in":["1.11.1-1ubuntu0.26.04.2"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Alpine:v3.24","package":"chromium-rust","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.96.1-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.21","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-r3"}]}]},{"source":"osv","ecosystem":"Alpine:v3.22","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-r3"}]}]},{"source":"osv","ecosystem":"Alpine:v3.23","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-r4"}]}]},{"source":"osv","ecosystem":"Alpine:v3.24","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-r4"}]}]},{"source":"osv","ecosystem":"Alpine:v3.24","package":"rust","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.96.1-r0"}]}]},{"source":"osv","ecosystem":"Azure Linux:3","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-4"}]}]},{"source":"osv","ecosystem":"Alpaquita:23","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.10.0-r4"},{"fixed":"1.11.1-r2"}]}]},{"source":"osv","ecosystem":"Alpaquita:25","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.11.1-r0"},{"fixed":"1.11.1-r3"}]}]},{"source":"osv","ecosystem":"Alpaquita:stream","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.10.0-r4"},{"fixed":"1.11.1-r4"}]}]},{"source":"osv","ecosystem":"Alpaquita:stream","package":"rust","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.69.0-r10"},{"fixed":"1.96.1-r0"}]}]},{"source":"osv","ecosystem":"TuxCare:Ubuntu:20.04","package":"libssh2-1","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.8.0-2.1ubuntu0.1+tuxcare.els4"}]}],"bundled":2},{"source":"osv","ecosystem":"TuxCare:Ubuntu:20.04","package":"libssh2-1-dev","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.8.0-2.1ubuntu0.1+tuxcare.els4"}]}],"bundled":2},{"source":"osv","ecosystem":"Debian:12","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.10.0-3+deb12u1"}]}],"versions":["1.10.0-3"]},{"source":"osv","ecosystem":"Debian:13","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-1+deb13u1"}]}],"versions":["1.11.1-1"]},{"source":"osv","ecosystem":"Debian:14","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-4"}]}],"versions":["1.11.1-1","1.11.1-2","1.11.1-3"]},{"source":"osv","ecosystem":"Julia","package":"LibSSH2_jll","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.11.102+0"}]}]},{"source":"osv","ecosystem":"Mageia:10","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-2.1.mga10"}]}],"bundled":6},{"source":"osv","ecosystem":"Mageia:9","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-1.1.mga9"}]}],"bundled":6},{"source":"osv","ecosystem":"openEuler:22.03-LTS-SP4","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.10.0-10.oe2203sp4"}]}],"bundled":2},{"source":"osv","ecosystem":"openEuler:24.03-LTS-SP1","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-7.oe2403sp1"}]}],"bundled":2},{"source":"osv","ecosystem":"openEuler:24.03-LTS-SP3","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-7.oe2403sp3"}]}],"bundled":2},{"source":"osv","ecosystem":"openEuler:20.03-LTS-SP4","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.9.0-12.oe2003sp4"}]}]},{"source":"osv","ecosystem":"openEuler:24.03-LTS-SP4","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-14.oe2403sp4"}]}],"bundled":6},{"source":"osv","ecosystem":"Red Hat:hummingbird:1","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:1.11.1-9.hum1"}]}]},{"source":"osv","ecosystem":"Red Hat:hummingbird:1","package":"libssh2-devel","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:1.11.1-9.hum1"}]}]},{"source":"osv","ecosystem":"Red Hat:hummingbird:1","package":"libssh2-docs","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:1.11.1-9.hum1"}]}]},{"source":"osv","ecosystem":"SUSE:Linux Micro 6.2","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-160000.5.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Micro 6.1","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-slfo.1.1_2.1"}]}],"bundled":9},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server 16.0","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-160000.5.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server for SAP applications 16.0","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-160000.5.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server 16.0","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-160000.5.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server for SAP applications 16.0","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-160000.5.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Micro 6.0","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-4.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server 12 SP5-LTSS","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-29.18.1"}]}],"bundled":9},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server LTSS Extended Security 12 SP5","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-29.18.1"}]}],"bundled":9},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Micro 5.3","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-150200.9.8.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Micro 5.4","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-150200.9.8.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Micro 5.5","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-150200.9.8.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-150200.9.8.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise High Performance Computing 15 SP4-LTSS","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-150200.9.8.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise High Performance Computing 15 SP5-ESPOS","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-150200.9.8.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise High Performance Computing 15 SP5-LTSS","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-150200.9.8.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server 15 SP4-LTSS","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-150200.9.8.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server 15 SP5-LTSS","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-150200.9.8.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server for SAP Applications 15 SP4","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-150200.9.8.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server for SAP Applications 15 SP5","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-150200.9.8.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Module for Basesystem 15 SP7","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-150600.20.6.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server 15 SP6-LTSS","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-150600.20.6.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server for SAP Applications 15 SP6","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-150600.20.6.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-150000.4.35.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise High Performance Computing 15 SP4-LTSS","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-150000.4.35.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server 15 SP4-LTSS","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-150000.4.35.1"}]}],"bundled":8},{"source":"osv","ecosystem":"Ubuntu:Pro:14.04:LTS","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.4.3-1","1.4.3-2","1.4.3-2ubuntu0.1","1.4.3-2ubuntu0.2","1.4.3-2ubuntu0.2+esm1","1.4.3-2ubuntu0.2+esm2","1.4.3-2ubuntu0.2+esm3","1.4.3-2ubuntu0.2+esm4"]},{"source":"osv","ecosystem":"Ubuntu:Pro:16.04:LTS","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.5.0-2","1.5.0-2ubuntu0.1","1.5.0-2ubuntu0.1+esm1","1.5.0-2ubuntu0.1+esm2","1.5.0-2ubuntu0.1+esm3"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.0-1","1.8.0-1ubuntu0.1","1.8.0-1ubuntu0.1+esm1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.0-2.1build1","1.8.0-2.1ubuntu0.1","1.8.0-2.1ubuntu0.1+esm1"]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.9.0-3","1.10.0-2","1.10.0-2build1","1.10.0-3","1.10.0-3ubuntu0.1"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-4.1ubuntu0.24.04.2"}]}],"versions":["1.11.0-2","1.11.0-3","1.11.0-4","1.11.0-4.1build1","1.11.0-4.1build2","1.11.0-4.1ubuntu0.24.04.1"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-1ubuntu0.25.10.2"}]}],"versions":["1.11.1-1","1.11.1-1build1","1.11.1-1ubuntu0.25.10.1"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-1ubuntu0.26.04.2"}]}],"versions":["1.11.1-1build1","1.11.1-1build2","1.11.1-1ubuntu0.26.04.1"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.0-4.1ubuntu0.24.04.2"}]}],"versions":["1.11.0-2","1.11.0-3","1.11.0-4","1.11.0-4.1build1","1.11.0-4.1build2","1.11.0-4.1ubuntu0.24.04.1"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-1ubuntu0.25.10.2"}]}],"versions":["1.11.1-1","1.11.1-1build1","1.11.1-1ubuntu0.25.10.1"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"libssh2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-1ubuntu0.26.04.2"}]}],"versions":["1.11.1-1build1","1.11.1-1build2","1.11.1-1ubuntu0.26.04.1"]},{"source":"osv","ecosystem":"openSUSE:Tumbleweed","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-3.1"}]}],"bundled":4},{"source":"osv","ecosystem":"openSUSE:Leap 16.0","package":"libssh2_org","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.11.1-160000.5.1"}]}],"bundled":8}],"products":[{"vendor":"libssh2","product":"libssh2"},{"vendor":"siemens","product":"simatic s7-1500 cpu 1518-4 pn/dp mfp (6es7518-4ax00-1ab0)"},{"vendor":"siemens","product":"simatic s7-1500 cpu 1518-4 pn/dp mfp (6es7518-4ax00-1ac0)"},{"vendor":"siemens","product":"simatic s7-1500 cpu 1518f-4 pn/dp mfp (6es7518-4fx00-1ab0)"},{"vendor":"siemens","product":"simatic s7-1500 cpu 1518f-4 pn/dp mfp (6es7518-4fx00-1ac0)"},{"vendor":"siemens","product":"siplus s7-1500 cpu 1518-4 pn/dp mfp (6ag1518-4ax00-4ac0)"}],"references":[{"url":"https://github.com/libssh2/libssh2/pull/1705","tags":["issue-tracking","patch","Patch","fix","web","article","report"]},{"url":"https://github.com/libssh2/libssh2/pull/1717","tags":["issue-tracking","patch","Patch","fix","web","article","report"]},{"url":"https://github.com/libssh2/libssh2/commit/2dae3024897e1898d389835151f4e9606227721d","tags":["patch","Patch","fix","web","article"]},{"url":"https://www.vulncheck.com/advisories/libssh2-heap-buffer-over-read-via-sftp-symlink-in-sftp-c","tags":["third-party-advisory","Third Party Advisory","advisory","web","article","report"]},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-457936.html","tags":["web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-15661","tags":["web","advisory"]},{"url":"https://github.com/advisories/GHSA-3wqh-87fg-ffgg","tags":["web"]},{"url":"https://security.alpinelinux.org/vuln/CVE-2025-15661","tags":["advisory"]},{"url":"https://docs.bell-sw.com/security/cves/CVE-2025-15661","tags":["advisory"]},{"url":"https://errata.tuxcare.com/els_os/ubuntu20.04els/CLSA-2026-1791823540.html","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-7598","tags":["advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/15xxx/CVE-2025-15661.json","tags":["advisory"]},{"url":"https://github.com/libssh2/libssh2","tags":["package"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2025-15661","tags":["advisory"]},{"url":"https://advisories.mageia.org/MGASA-2026-0273.html","tags":["advisory"]},{"url":"https://bugs.mageia.org/show_bug.cgi?id=35616","tags":["report"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NRU63FODXZBBO73NFWUI32A2A36ETDQZ/","tags":["web"]},{"url":"https://www.openwall.com/lists/oss-security/2026/06/23/10","tags":["web"]},{"url":"https://www.openwall.com/lists/oss-security/2026/06/23/11","tags":["web"]},{"url":"https://lists.debian.org/debian-security-announce/2026/msg00276.html","tags":["web"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZREI4LITT4U2ZXPEEVVNALFKPLXGLAFM/","tags":["web"]},{"url":"https://lists.opensuse.org/archives/list/security-announce@lists.opensuse.org/message/SRBHQ76PA4ZHTWY5F4ESYPYF3G2NLGWI/","tags":["web"]},{"url":"https://ubuntu.com/security/notices/USN-8486-1","tags":["advisory"]},{"url":"https://ubuntu.com/security/notices/USN-8532-1","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-3014","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-55199","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-3015","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-3016","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-3017","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-3479","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-58050","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-66032","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-66033","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-66034","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-66035","tags":["advisory"]},{"url":"https://access.redhat.com/errata/RHSA-2026:30132","tags":["advisory"]},{"url":"https://images.redhat.com/","tags":["article"]},{"url":"https://access.redhat.com/security/cve/CVE-2025-15661","tags":["report"]},{"url":"https://access.redhat.com/security/updates/classification/","tags":["article"]},{"url":"https://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_30132.json","tags":["advisory"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2490586","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2025-15661","tags":["advisory","report"]},{"url":"https://www.suse.com/support/update/announcement/2026/suse-su-202623049-1/","tags":["advisory"]},{"url":"https://bugzilla.suse.com/1263890","tags":["report"]},{"url":"https://bugzilla.suse.com/1268546","tags":["report"]},{"url":"https://bugzilla.suse.com/1269567","tags":["report"]},{"url":"https://bugzilla.suse.com/1269568","tags":["report"]},{"url":"https://bugzilla.suse.com/1272734","tags":["report"]},{"url":"https://bugzilla.suse.com/1272735","tags":["report"]},{"url":"https://bugzilla.suse.com/1272736","tags":["report"]},{"url":"https://bugzilla.suse.com/1272737","tags":["report"]},{"url":"https://www.suse.com/security/cve/CVE-2025-15661","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-58050","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-58051","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-66032","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-66033","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-66034","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-66035","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-7598","tags":["web"]},{"url":"https://www.suse.com/support/update/announcement/2026/suse-su-202623187-1/","tags":["advisory"]},{"url":"https://bugzilla.suse.com/1268530","tags":["report"]},{"url":"https://www.suse.com/security/cve/CVE-2026-55199","tags":["web"]},{"url":"https://www.suse.com/support/update/announcement/2026/suse-su-202623214-1/","tags":["advisory"]},{"url":"https://www.suse.com/support/update/announcement/2026/suse-su-202623225-1/","tags":["advisory"]},{"url":"https://www.suse.com/support/update/announcement/2026/suse-su-202623245-1/","tags":["advisory"]},{"url":"https://bugzilla.suse.com/1218971","tags":["report"]},{"url":"https://bugzilla.suse.com/1221622","tags":["report"]},{"url":"https://www.suse.com/support/update/announcement/2026/suse-su-20263525-1/","tags":["advisory"]},{"url":"https://www.suse.com/support/update/announcement/2026/suse-su-20263526-1/","tags":["advisory"]},{"url":"https://www.suse.com/support/update/announcement/2026/suse-su-20263541-1/","tags":["advisory"]},{"url":"https://www.suse.com/support/update/announcement/2026/suse-su-20264095-1/","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2025-15661","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2026-55199","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2026-55200","tags":["report"]},{"url":"","tags":["advisory"]},{"url":"https://www.suse.com/security/cve/CVE-2026-55200","tags":["web"]}],"sources":{"cve":[{"id":"CVE-2025-15661","title":"libssh2 - Heap Buffer Over-read via sftp_symlink() in sftp.c","description":"libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.","status":"published","published":"2026-06-18T20:18:29.475Z","modified":"2026-11-10T12:34:26.947Z","cvss":[{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high","assessor":"cna"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H","level":"medium","assessor":"cna"}],"cwes":["CWE-125"],"updated_at":"2026-11-10T13:38:44.039016Z"}],"euvd":[{"id":"EUVD-2025-210285","description":"libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.","status":"published","published":"2026-06-18T20:18:29Z","modified":"2026-11-10T12:34:26Z","cvss":[{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-08T15:13:10.25084Z"}],"ghsa":[{"id":"GHSA-3wqh-87fg-ffgg","title":"libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read...","description":"libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.","status":"published","published":"2026-06-18T21:32:35Z","modified":"2026-11-10T15:32:44Z","cvss":[{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H","level":"medium"}],"cwes":["CWE-125"],"updated_at":"2026-11-10T15:55:01.006697Z"}],"nvd":[{"id":"CVE-2025-15661","description":"libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.","status":"published","published":"2026-06-18T21:16:27.143Z","modified":"2026-11-10T13:17:31.627Z","cvss":[{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H","level":"medium","assessor":"secondary"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H","level":"medium","assessor":"primary"}],"cwes":["CWE-125"],"updated_at":"2026-11-10T16:19:46.886348Z"}],"osv":[{"id":"ALPINE-CVE-2025-15661","description":"libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.","status":"published","published":"2026-06-18T21:16:27.143Z","modified":"2026-11-03T06:33:00.235764765Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H","level":"medium"}],"updated_at":"2026-11-03T07:16:09.603409Z"},{"id":"BELL-CVE-2025-15661","status":"published","published":"2026-06-23T06:12:36.517069Z","modified":"2026-07-09T07:15:04.016824027Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:28:21.227396Z"},{"id":"CVE-2025-15661","title":"libssh2 - Heap Buffer Over-read via sftp_symlink() in sftp.c","description":"libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.","status":"published","published":"2026-06-18T20:18:29.475Z","modified":"2026-11-12T07:06:28.86967007Z","cvss":[{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"cwes":["CWE-125"],"updated_at":"2026-11-11T03:22:28.447808Z"},{"id":"DEBIAN-CVE-2025-15661","description":"libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.","status":"published","published":"2026-06-18T21:16:27.143Z","modified":"2026-11-11T09:47:39.17960449Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H","level":"medium"}],"updated_at":"2026-11-11T10:35:40.696585Z"},{"id":"JLSEC-2026-659","title":"libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability...","description":"libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the `sftp_symlink()` function in `src/sftp.c` that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted `SSH_FXP_NAME` response. Attackers can supply a `link_len` value larger than the actual packet data in `SSH_FXP_NAME` responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to `target_len` minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.","status":"published","published":"2026-07-10T13:57:40.607Z","modified":"2026-07-25T18:24:44.149902602Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H","level":"medium"},{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high"}],"updated_at":"2026-11-02T15:47:19.003546Z"},{"id":"OESA-2026-3014","title":"libssh2 security update","description":"libssh2 is a library implementing the SSH2 protocol as defined by Internet Drafts: SECSH-TRANS(22), SECSH-USERAUTH(25), SECSH-CONNECTION(23), SECSH-ARCH(20), SECSH-FILEXFER(06)*, SECSH-DHGEX(04), and SECSH-NUMBERS(10).\r\n\r\nSecurity Fix(es):\n\nlibssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.(CVE-2025-15661)\n\nlibssh2 through 1.11.1, fixed in commit 1762685, contains a pre-authentication denial of service vulnerability in the SSH_MSG_EXT_INFO handler in src/packet.c that allows a malicious SSH server to cause a client CPU exhaustion loop by sending a crafted extension count value. A malicious server can set nr_extensions to 0xFFFFFFFF during key exchange, causing the client to spin in a tight CPU loop for over 60 seconds because return values from _libssh2_get_string() are unchecked and the session timeout does not apply to CPU-bound loops.(CVE-2026-55199)","status":"published","published":"2026-07-19T11:11:54Z","modified":"2026-08-18T01:21:18.167850902Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T15:52:46.823443Z"},{"id":"OESA-2026-3015","title":"libssh2 security update","description":"libssh2 is a library implementing the SSH2 protocol as defined by Internet Drafts: SECSH-TRANS(22), SECSH-USERAUTH(25), SECSH-CONNECTION(23), SECSH-ARCH(20), SECSH-FILEXFER(06)*, SECSH-DHGEX(04), and SECSH-NUMBERS(10).\r\n\r\nSecurity Fix(es):\n\nlibssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.(CVE-2025-15661)\n\nlibssh2 through 1.11.1, fixed in commit 1762685, contains a pre-authentication denial of service vulnerability in the SSH_MSG_EXT_INFO handler in src/packet.c that allows a malicious SSH server to cause a client CPU exhaustion loop by sending a crafted extension count value. A malicious server can set nr_extensions to 0xFFFFFFFF during key exchange, causing the client to spin in a tight CPU loop for over 60 seconds because return values from _libssh2_get_string() are unchecked and the session timeout does not apply to CPU-bound loops.(CVE-2026-55199)","status":"published","published":"2026-07-19T11:11:54Z","modified":"2026-08-18T01:21:18.224163303Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T15:52:46.823443Z"},{"id":"OESA-2026-3016","title":"libssh2 security update","description":"libssh2 is a library implementing the SSH2 protocol as defined by Internet Drafts: SECSH-TRANS(22), SECSH-USERAUTH(25), SECSH-CONNECTION(23), SECSH-ARCH(20), SECSH-FILEXFER(06)*, SECSH-DHGEX(04), and SECSH-NUMBERS(10).\r\n\r\nSecurity Fix(es):\n\nlibssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.(CVE-2025-15661)\n\nlibssh2 through 1.11.1, fixed in commit 1762685, contains a pre-authentication denial of service vulnerability in the SSH_MSG_EXT_INFO handler in src/packet.c that allows a malicious SSH server to cause a client CPU exhaustion loop by sending a crafted extension count value. A malicious server can set nr_extensions to 0xFFFFFFFF during key exchange, causing the client to spin in a tight CPU loop for over 60 seconds because return values from _libssh2_get_string() are unchecked and the session timeout does not apply to CPU-bound loops.(CVE-2026-55199)","status":"published","published":"2026-07-19T11:11:54Z","modified":"2026-08-18T01:21:18.168342472Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T15:52:46.823443Z"},{"id":"OESA-2026-3017","title":"libssh2 security update","description":"libssh2 is a library implementing the SSH2 protocol as defined by Internet Drafts: SECSH-TRANS(22), SECSH-USERAUTH(25), SECSH-CONNECTION(23), SECSH-ARCH(20), SECSH-FILEXFER(06)*, SECSH-DHGEX(04), and SECSH-NUMBERS(10).\r\n\r\nSecurity Fix(es):\n\nlibssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.(CVE-2025-15661)","status":"published","published":"2026-07-19T11:11:54Z","modified":"2026-08-18T01:21:19.711799516Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:52:46.823443Z"},{"id":"OESA-2026-3479","title":"libssh2 security update","description":"libssh2 is a library implementing the SSH2 protocol as defined by Internet Drafts: SECSH-TRANS(22), SECSH-USERAUTH(25), SECSH-CONNECTION(23), SECSH-ARCH(20), SECSH-FILEXFER(06)*, SECSH-DHGEX(04), and SECSH-NUMBERS(10).\r\n\r\nSecurity Fix(es):\n\nlibssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.(CVE-2025-15661)\n\nlibssh2 through 1.11.1 reads an attacker-controlled 32-bit attribute count from a publickey-subsystem response and uses it in the allocation num_attrs * sizeof(libssh2_publickey_attribute) without bounds checking, so on 32-bit platforms the multiplication overflows to an undersized buffer. A malicious SSH server can then drive the attribute-parsing loop to write past the allocation, causing a heap buffer overflow in a connecting libssh2 client.(CVE-2026-58050)\n\nlibssh2 through 1.11.1, fixed in commit 5e47761, contains a double-free vulnerability in the sftp_open() function in src/sftp.c that allows a malicious SSH server to corrupt the heap of any authenticated client opening an SFTP session. When a server responds to SSH_FXP_OPEN with SSH_FXP_STATUS containing FX_OK, the response data buffer is freed, and if a subsequent sftp_packet_require() call returns a specific error such as LIBSSH2_ERROR_CHANNEL_PACKET_EXCEEDED, the same pointer is freed a second time, enabling tcache dup conditions on glibc systems that allow overlapping allocations and function pointer overwrites.(CVE-2026-66032)\n\nlibssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2_cipher_crypt() function in src/openssl.c that allows a malicious SSH server to crash any connecting client by negotiating AES-GCM ciphers during handshake. Attackers can exploit the underflow in the expression computing blocksize minus aadlen minus authentication tag length to trigger an out-of-bounds read and a memcpy call with a near-SIZE_MAX length argument, causing immediate process crash before any authentication occurs.(CVE-2026-66033)\n\nlibssh2 through 1.11.1, fixed in commit a13bb6c, contains a missing bounds check vulnerability that allows a malicious SSH server to trigger an arbitrary-length heap out-of-bounds read and a free of an uninitialized pointer via the publickey subsystem. In libssh2_publickey_list_fetch(), the version 1 response parser reads a server-controlled comment_len value and advances the parse pointer without verifying sufficient bytes remain in the buffer, causing the out-of-bounds read to leak heap pointers from adjacent allocations defeating ASLR, followed by heap allocator state corruption when the error cleanup path frees an uninitialized pointer from a non-zeroed realloc() region.(CVE-2026-66034)\n\nlibssh2 through 1.11.1, fixed in commit 42e33d8, contains a pre-authentication heap buffer overflow vulnerability that allows a malicious SSH server to corrupt heap metadata in any connecting client by sending a packet with a packet_length smaller than the cipher\u0026apos;s block size during Encrypt-then-MAC cipher negotiation. In the fullpacket() function in src/transport.c, the ETM path allocates a buffer of packet_length bytes but copies blocksize minus one bytes via memcpy, causing an overflow that on 32-bit glibc writes attacker-controlled bytes into an adjacent chunk\u0026apos;s SIZE field, enabling tcache bin confusion, overlapping live objects, and function pointer overwrite during the session handshake before authentication.(CVE-2026-66035)","status":"published","published":"2026-08-20T10:01:10Z","modified":"2026-08-20T10:15:04.95517507Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:52:47.217107Z"},{"id":"RHSA-2026:30132","title":"Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update","status":"published","published":"2026-06-27T10:25:28Z","modified":"2026-10-06T10:31:23.050362991Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:53:19.963895Z"},{"id":"UBUNTU-CVE-2025-15661","description":"libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.","status":"published","published":"2026-06-18T21:16:00Z","modified":"2026-09-22T15:33:10.185552582Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H","level":"medium"},{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H","level":"medium"},{"version":"4.0","score":8.3,"vector":"CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T16:55:20.144818Z"},{"id":"AZL-90936","title":"CVE-2025-15661 affecting package libssh2 for versions less than 1.11.1-4","description":"libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSH_FXP_NAME response. Attackers can supply a link_len value larger than the actual packet data in SSH_FXP_NAME responses for SFTP READLINK and REALPATH operations, triggering a heap buffer over-read of up to target_len minus one bytes due to the missing validation of available packet buffer size before the memcpy operation.","status":"published","published":"2026-06-18T21:16:27Z","modified":"2026-11-05T05:40:51Z","updated_at":"2026-11-05T16:41:25.633663Z"},{"id":"CLSA-2026-1791823540","title":"Fix CVE(s): CVE-2025-15661, CVE-2026-7598","description":"   * SECURITY UPDATE: out-of-bounds heap read in SFTP symlink handling\n     - debian/patches/CVE-2025-15661.patch: validate that the link length\n       in a SSH_FXP_NAME response fits within the received packet before\n       copying it in sftp_symlink() in src/sftp.c\n     - CVE-2025-15661","status":"published","published":"2026-10-19T15:58:53Z","modified":"2026-10-26T09:32:05.636747957Z","updated_at":"2026-11-02T15:43:50.599064Z"},{"id":"MGASA-2026-0273","title":"Updated libssh2 packages fix security vulnerabilities","description":"The updated packages fix security vulnerabilities:\nHeap Buffer Over-read via sftp_symlink() in sftp.c. (CVE-2025-15661)\nlibssh2 userauth.c userauth_password integer overflow. (CVE-2026-7598)\nPre-Authentication DoS via SSH_MSG_EXT_INFO Handler. (CVE-2026-55199)\nOut-of-Bounds Write via Unchecked packet_length in transport.c.\n(CVE-2026-55200)\nInteger Overflow in publickey Subsystem Attribute Allocation.\n(CVE-2026-58050)\nFree of Uninitialized Pointer in publickey List Cleanup.\n(CVE-2026-58051)\n","status":"published","published":"2026-07-20T19:06:32Z","modified":"2026-07-20T19:20:56.035464062Z","updated_at":"2026-11-02T15:49:43.795591Z"},{"id":"openSUSE-SU-2026:11109-1","title":"libssh2-1-1.11.1-3.1 on GA media","description":"These are all security issues fixed in the libssh2-1-1.11.1-3.1 package on the GA media of openSUSE Tumbleweed.","status":"published","published":"2026-06-23T00:00:00Z","modified":"2026-06-24T09:00:05.16911932Z","updated_at":"2026-11-02T16:58:38.95195Z"},{"id":"openSUSE-SU-2026:21549-1","title":"Security update for libssh2_org","description":"This update for libssh2_org fixes the following issues:\n\n- CVE-2025-15661: out-of-bounds heap read vulnerability in the `sftp_symlink()` function in `src/sftp.c` (bsc#1268546).\n- CVE-2026-7598: integer overflow in function `userauth_password` of file `src/userauth.c` (bsc#1263890).\n- CVE-2026-58050: heap buffer overflow due to missing bounds check in attribute count of publickey-subsystem response\n  (bsc#1269568).\n- CVE-2026-58051: uninitialized pointer freed when malformed responses are sent by an SSH server (bsc#1269567).\n- CVE-2026-66032: arbitrary code execution via double-free in SFTP session (bsc#1272737).\n- CVE-2026-66033: denial of service via integer underflow in AES-GCM cipher negotiation (bsc#1272736).\n- CVE-2026-66034: information disclosure and potential arbitrary code execution via heap out-of-bounds read\n  (bsc#1272735).\n- CVE-2026-66035: arbitrary code execution via heap buffer overflow during SSH negotiation (bsc#1272734).\n","status":"published","published":"2026-08-10T15:24:32Z","modified":"2026-08-12T18:23:41.472675266Z","updated_at":"2026-11-02T16:58:41.885092Z"},{"id":"ROOT-OS-DEBIAN-12-CVE-2025-15661","title":"CVE-2025-15661 in libssh2 - Patched by Root","description":"Root has patched CVE-2025-15661 in the libssh2 package for Root:Debian:12. Multiple fixed versions available.","status":"withdrawn","published":"2026-08-25T11:14:15Z","modified":"2026-09-07T08:00:08.136293578Z","updated_at":"2026-11-02T15:53:30.983521Z"},{"id":"SUSE-SU-2026:23049-1","title":"Security update for libssh2_org","description":"This update for libssh2_org fixes the following issues:\n\n- CVE-2025-15661: out-of-bounds heap read vulnerability in the `sftp_symlink()` function in `src/sftp.c` (bsc#1268546).\n- CVE-2026-7598: integer overflow in function `userauth_password` of file `src/userauth.c` (bsc#1263890).\n- CVE-2026-58050: heap buffer overflow due to missing bounds check in attribute count of publickey-subsystem response\n  (bsc#1269568).\n- CVE-2026-58051: uninitialized pointer freed when malformed responses are sent by an SSH server (bsc#1269567).\n- CVE-2026-66032: arbitrary code execution via double-free in SFTP session (bsc#1272737).\n- CVE-2026-66033: denial of service via integer underflow in AES-GCM cipher negotiation (bsc#1272736).\n- CVE-2026-66034: information disclosure and potential arbitrary code execution via heap out-of-bounds read\n  (bsc#1272735).\n- CVE-2026-66035: arbitrary code execution via heap buffer overflow during SSH negotiation (bsc#1272734).\n","status":"published","published":"2026-08-10T15:24:14Z","modified":"2026-08-12T10:45:03.527208296Z","updated_at":"2026-11-02T15:54:03.503431Z"},{"id":"SUSE-SU-2026:23187-1","title":"Security update for libssh2_org","description":"This update for libssh2_org fixes the following issues:\n\n- CVE-2025-15661: out-of-bounds heap read vulnerability in the `sftp_symlink()` function in `src/sftp.c` (bsc#1268546).\n- CVE-2026-7598: integer overflow in function `userauth_password` of file `src/userauth.c` (bsc#1263890).\n- CVE-2026-55199: pre-authentication DoS via the `SSH_MSG_EXT_INFO` handler (bsc#1268530).\n- CVE-2026-58050: heap buffer overflow due to missing bounds check in attribute count of publickey-subsystem response\n  (bsc#1269568).\n- CVE-2026-58051: uninitialized pointer freed when malformed responses are sent by an SSH server (bsc#1269567).\n- CVE-2026-66032: arbitrary code execution via double-free in SFTP session (bsc#1272737).\n- CVE-2026-66033: denial of service via integer underflow in AES-GCM cipher negotiation (bsc#1272736).\n- CVE-2026-66034: information disclosure and potential arbitrary code execution via heap out-of-bounds read\n  (bsc#1272735).\n- CVE-2026-66035: arbitrary code execution via heap buffer overflow during SSH negotiation (bsc#1272734).\n","status":"published","published":"2026-08-17T16:37:24Z","modified":"2026-08-26T18:23:31.171326675Z","updated_at":"2026-11-02T15:54:03.503431Z"},{"id":"SUSE-SU-2026:23214-1","title":"Security update for libssh2_org","description":"This update for libssh2_org fixes the following issues:\n\n- CVE-2025-15661: out-of-bounds heap read vulnerability in the `sftp_symlink()` function in `src/sftp.c` (bsc#1268546).\n- CVE-2026-7598: integer overflow in function `userauth_password` of file `src/userauth.c` (bsc#1263890).\n- CVE-2026-58050: heap buffer overflow due to missing bounds check in attribute count of publickey-subsystem response\n  (bsc#1269568).\n- CVE-2026-58051: uninitialized pointer freed when malformed responses are sent by an SSH server (bsc#1269567).\n- CVE-2026-66032: arbitrary code execution via double-free in SFTP session (bsc#1272737).\n- CVE-2026-66033: denial of service via integer underflow in AES-GCM cipher negotiation (bsc#1272736).\n- CVE-2026-66034: information disclosure and potential arbitrary code execution via heap out-of-bounds read\n  (bsc#1272735).\n- CVE-2026-66035: arbitrary code execution via heap buffer overflow during SSH negotiation (bsc#1272734).\n","status":"published","published":"2026-08-10T15:24:14Z","modified":"2026-08-27T18:23:09.163427698Z","updated_at":"2026-11-02T15:54:03.503431Z"},{"id":"SUSE-SU-2026:23225-1","title":"Security update for libssh2_org","description":"This update for libssh2_org fixes the following issues:\n\n- CVE-2025-15661: out-of-bounds heap read vulnerability in the `sftp_symlink()` function in `src/sftp.c` (bsc#1268546).\n- CVE-2026-7598: integer overflow in function `userauth_password` of file `src/userauth.c` (bsc#1263890).\n- CVE-2026-58050: heap buffer overflow due to missing bounds check in attribute count of publickey-subsystem response\n  (bsc#1269568).\n- CVE-2026-58051: uninitialized pointer freed when malformed responses are sent by an SSH server (bsc#1269567).\n- CVE-2026-66032: arbitrary code execution via double-free in SFTP session (bsc#1272737).\n- CVE-2026-66033: denial of service via integer underflow in AES-GCM cipher negotiation (bsc#1272736).\n- CVE-2026-66034: information disclosure and potential arbitrary code execution via heap out-of-bounds read\n  (bsc#1272735).\n- CVE-2026-66035: arbitrary code execution via heap buffer overflow during SSH negotiation (bsc#1272734).\n","status":"published","published":"2026-08-10T15:24:14Z","modified":"2026-08-27T18:23:10.117559844Z","updated_at":"2026-11-02T15:54:03.503431Z"},{"id":"SUSE-SU-2026:23245-1","title":"Security update for libssh2_org","description":"This update for libssh2_org fixes the following issues:\n\nSecurity issues fixed:\n\n- CVE-2025-15661: out-of-bounds heap read vulnerability in the `sftp_symlink()` function in `src/sftp.c` (bsc#1268546).\n- CVE-2026-7598: integer overflow in function `userauth_password` of file `src/userauth.c` (bsc#1263890).\n- CVE-2026-58050: heap buffer overflow due to missing bounds check in attribute count of publickey-subsystem response\n  (bsc#1269568).\n- CVE-2026-58051: uninitialized pointer freed when malformed responses are sent by an SSH server (bsc#1269567).\n- CVE-2026-66032: arbitrary code execution via double-free in SFTP session (bsc#1272737).\n- CVE-2026-66033: denial of service via integer underflow in AES-GCM cipher negotiation (bsc#1272736).\n- CVE-2026-66034: information disclosure and potential arbitrary code execution via heap out-of-bounds read\n  (bsc#1272735).\n- CVE-2026-66035: arbitrary code execution via heap buffer overflow during SSH negotiation (bsc#1272734).\n\nOther updates and bugfixes:\n\n- Fix an issue with Encrypt-then-MAC family (bsc#1221622).\n  * Test the ETM feature in the remote end's configuration when receiving data. Upstream issue: #1331.\n- Always add the KEX pseudo-methods `ext-info-c` and `kex-strict-c-v00@openssh.com` when configuring custom method list\n  (bsc#1218971).\n  * The strict-kex extension is announced in the list of available KEX methods. However, when the default KEX method\n    list is modified or replaced, the extension is not added back automatically.\n","status":"published","published":"2026-08-19T10:47:36Z","modified":"2026-08-27T18:23:11.283934635Z","updated_at":"2026-11-02T15:54:03.503431Z"},{"id":"SUSE-SU-2026:3525-1","title":"Security update for libssh2_org","description":"This update for libssh2_org fixes the following issues:\n\n- CVE-2025-15661: out-of-bounds heap read vulnerability in the `sftp_symlink()` function in `src/sftp.c` (bsc#1268546).\n- CVE-2026-7598: integer overflow in function `userauth_password` of file `src/userauth.c` (bsc#1263890).\n- CVE-2026-55199: pre-authentication DoS via the `SSH_MSG_EXT_INFO` handler (bsc#1268530).\n- CVE-2026-58050: heap buffer overflow due to missing bounds check in attribute count of publickey-subsystem response\n  (bsc#1269568).\n- CVE-2026-58051: uninitialized pointer freed when malformed responses are sent by an SSH server (bsc#1269567).\n- CVE-2026-66032: arbitrary code execution via double-free in SFTP session (bsc#1272737).\n- CVE-2026-66033: denial of service via integer underflow in AES-GCM cipher negotiation (bsc#1272736).\n- CVE-2026-66034: information disclosure and potential arbitrary code execution via heap out-of-bounds read\n  (bsc#1272735).\n- CVE-2026-66035: arbitrary code execution via heap buffer overflow during SSH negotiation (bsc#1272734).\n","status":"published","published":"2026-08-07T13:08:26Z","modified":"2026-08-08T09:00:06.084070296Z","updated_at":"2026-11-02T15:54:04.987808Z"},{"id":"SUSE-SU-2026:3526-1","title":"Security update for libssh2_org","description":"This update for libssh2_org fixes the following issues:\n\n- CVE-2025-15661: out-of-bounds heap read vulnerability in the `sftp_symlink()` function in `src/sftp.c` (bsc#1268546).\n- CVE-2026-7598: integer overflow in function `userauth_password` of file `src/userauth.c` (bsc#1263890).\n- CVE-2026-58050: heap buffer overflow due to missing bounds check in attribute count of publickey-subsystem response\n  (bsc#1269568).\n- CVE-2026-58051: uninitialized pointer freed when malformed responses are sent by an SSH server (bsc#1269567).\n- CVE-2026-66032: arbitrary code execution via double-free in SFTP session (bsc#1272737).\n- CVE-2026-66033: denial of service via integer underflow in AES-GCM cipher negotiation (bsc#1272736).\n- CVE-2026-66034: information disclosure and potential arbitrary code execution via heap out-of-bounds read\n  (bsc#1272735).\n- CVE-2026-66035: arbitrary code execution via heap buffer overflow during SSH negotiation (bsc#1272734).\n","status":"published","published":"2026-08-07T13:09:52Z","modified":"2026-08-08T09:00:06.060355593Z","updated_at":"2026-11-02T15:54:04.987808Z"},{"id":"SUSE-SU-2026:3541-1","title":"Security update for libssh2_org","description":"This update for libssh2_org fixes the following issues:\n\n- CVE-2025-15661: out-of-bounds heap read vulnerability in the `sftp_symlink()` function in `src/sftp.c` (bsc#1268546).\n- CVE-2026-7598: integer overflow in function `userauth_password` of file `src/userauth.c` (bsc#1263890).\n- CVE-2026-58050: heap buffer overflow due to missing bounds check in attribute count of publickey-subsystem response\n  (bsc#1269568).\n- CVE-2026-58051: uninitialized pointer freed when malformed responses are sent by an SSH server (bsc#1269567).\n- CVE-2026-66032: arbitrary code execution via double-free in SFTP session (bsc#1272737).\n- CVE-2026-66033: denial of service via integer underflow in AES-GCM cipher negotiation (bsc#1272736).\n- CVE-2026-66034: information disclosure and potential arbitrary code execution via heap out-of-bounds read\n  (bsc#1272735).\n- CVE-2026-66035: arbitrary code execution via heap buffer overflow during SSH negotiation (bsc#1272734).\n","status":"published","published":"2026-08-10T12:50:14Z","modified":"2026-08-11T09:15:07.240632328Z","updated_at":"2026-11-02T15:54:05.392906Z"},{"id":"SUSE-SU-2026:4095-1","title":"Security update for libssh2_org","description":"This update for libssh2_org fixes the following issues:\n\n- CVE-2025-15661: out-of-bounds heap read vulnerability in the sftp_symlink() function in src/sftp.c (bsc#1268546).\n- CVE-2026-7598: integer overflow in function `userauth_password` of file `src/userauth.c` (bsc#1263890).\n- CVE-2026-58050: attacker controlled attribute count from a publickey-subsystem response is used without bounds\n  checking and can cause to a heap buffer overflow in a connecting libssh2 client (bsc#1269568).\n- CVE-2026-58051: public key list is increased and does not zero-initialized new entries, which can cause an\n  uninitialized pointer to be freed when a malformed response is sent by an SSH server (bsc#1269567).\n- CVE-2026-66032: Arbitrary code execution via double-free in SFTP session (bsc#1272737).\n- CVE-2026-66033: Denial of Service via integer underflow in AES-GCM cipher negotiation (bsc#1272736).\n- CVE-2026-66034: Information disclosure and potential arbitrary code execution via heap out-of-bounds read\n  (bsc#1272735).\n- CVE-2026-66035: Arbitrary code execution via heap buffer overflow during SSH negotiation (bsc#1272734).\n","status":"published","published":"2026-09-09T08:34:01Z","modified":"2026-09-14T18:23:15.58672002Z","updated_at":"2026-11-02T15:54:05.392906Z"},{"id":"USN-8486-1","title":"libssh2 vulnerabilities","description":"It was discovered that libssh2 incorrectly handled the sftp_symlink()\nfunction. A malicious SSH server or machine-in-the-middle attacker could\npossibly use this issue to obtain sensitive information or cause a denial\nof service. (CVE-2025-15661)\n\nIt was discovered that libssh2 had a pre-authentication denial of service\nvulnerability in the SSH_MSG_EXT_INFO handler. A malicious SSH server could\npossibly use this issue to cause a client CPU exhaustion loop, resulting in\na denial of service. (CVE-2026-55199)\n\nIt was discovered that libssh2 incorrectly handled packet length fields. A\nremote attacker could possibly use this issue to execute arbitrary code.\nThis issue only affected Ubuntu 25.10 and Ubuntu 26.04 LTS.\n(CVE-2026-55200)","status":"published","published":"2026-06-30T12:41:51Z","modified":"2026-07-01T23:32:46.286503436Z","updated_at":"2026-11-02T16:58:25.103481Z"}]}}