{"id":"CVE-2026-34582","aliases":["ALPINE-CVE-2026-34582","AZL-81942","DEBIAN-CVE-2026-34582","EUVD-2026-19948","GHSA-pxcj-9ppx-g86g","UBUNTU-CVE-2026-34582","openSUSE-SU-2026:20528-1"],"status":"published","title":"Botan has a TLS 1.3 certificate authentication bypass","description":"Botan is a C++ cryptography library. Prior to version 3.11.1, the TLS 1.3 implementation allowed ApplicationData records to be processed prior to the Finished message being received. A server which is attempting to enforce client authentication via certificates can by bypassed by a client which entirely omits Certificate, CertificateVerify, and the Finished message and instead sends application data records. This vulnerability is fixed in 3.11.1.","severity":{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00242,"percentile":0.15516,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-166","CWE-841"],"published":"2026-04-07T21:13:49Z","modified":"2026-11-05T05:36:30Z","fixes":[{"ecosystem":"Alpine:v3.24","package":"botan3","fixed_in":["3.11.1-r0"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"botan3","fixed_in":["3.11.0+dfsg-2"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"botan3","fixed_in":["3.11.0+dfsg-2"],"sources":["osv"]},{"ecosystem":"openSUSE:Leap 16.0","package":"Botan","fixed_in":["3.7.1-160000.3.1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Alpine:v3.24","package":"botan3","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.11.1-r0"}]}]},{"source":"osv","ecosystem":"Azure Linux:3","package":"botan2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"2.14.0-2"}]}]},{"source":"osv","ecosystem":"Debian:13","package":"botan3","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.11.0+dfsg-2"}]}],"versions":["3.10.0+dfsg-1","3.10.0+dfsg-2","3.11.0+dfsg-1","3.7.1+dfsg-2","3.8.1+dfsg-1","3.9.0+dfsg-1","3.9.0+dfsg-2","3.9.0+dfsg-2.1"]},{"source":"osv","ecosystem":"Debian:14","package":"botan3","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.11.0+dfsg-2"}]}],"versions":["3.10.0+dfsg-1","3.10.0+dfsg-2","3.11.0+dfsg-1","3.7.1+dfsg-2","3.8.1+dfsg-1","3.9.0+dfsg-1","3.9.0+dfsg-2","3.9.0+dfsg-2.1"]},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"botan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.4.0-3","2.4.0-4","2.4.0-5ubuntu1"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"botan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.9.0-2","2.9.0-2build1","2.12.1-2","2.12.1-2build1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:22.04:LTS","package":"botan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.17.3+dfsg-3","2.19.1+dfsg-2ubuntu1","2.19.1+dfsg-2ubuntu1+esm1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:24.04:LTS","package":"botan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.19.3+dfsg-1ubuntu1","2.19.3+dfsg-1ubuntu2","2.19.3+dfsg-1ubuntu2+esm1"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"botan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.19.5+dfsg-4"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"botan3","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.7.1+dfsg-2"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"botan3","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.10.0+dfsg-2","3.11.1+dfsg-2","3.12.0+dfsg-2"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"botan3","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.7.1+dfsg-2","3.10.0+dfsg-2"]},{"source":"osv","ecosystem":"openSUSE:Leap 16.0","package":"Botan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.7.1-160000.3.1"}]}]}],"products":[{"vendor":"botan_project","product":"botan"},{"vendor":"randombit","product":"botan"},{"vendor":"red hat","product":"red hat enterprise linux 10"}],"references":[{"url":"https://github.com/randombit/botan/security/advisories/GHSA-pxcj-9ppx-g86g","tags":["x_refsource_CONFIRM","Mitigation","Vendor Advisory","advisory","report"]},{"url":"https://access.redhat.com/security/cve/CVE-2026-34582","tags":["vdb-entry","x_refsource_REDHAT","advisory"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2456285","tags":["issue-tracking","x_refsource_REDHAT","report"]},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-34582.json","tags":["x_sadp-csaf-vex","web"]},{"url":"https://security.alpinelinux.org/vuln/CVE-2026-34582","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-34582","tags":["web","advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34582.json","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-34582","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-34582","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-34582","tags":["report"]},{"url":"https://github.com/randombit/botan/pull/5599","tags":["report"]},{"url":"","tags":["advisory"]},{"url":"https://bugzilla.suse.com/1261880","tags":["report"]},{"url":"https://www.suse.com/security/cve/CVE-2026-34582","tags":["web"]}],"sources":{"cve":[{"id":"CVE-2026-34582","title":"Botan has a TLS 1.3 certificate authentication bypass","description":"Botan is a C++ cryptography library. Prior to version 3.11.1, the TLS 1.3 implementation allowed ApplicationData records to be processed prior to the Finished message being received. A server which is attempting to enforce client authentication via certificates can by bypassed by a client which entirely omits Certificate, CertificateVerify, and the Finished message and instead sends application data records. This vulnerability is fixed in 3.11.1.","status":"published","published":"2026-04-07T21:13:49.281Z","modified":"2026-07-15T01:04:16.798Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N","level":"high","assessor":"cna"},{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical","assessor":"adp"}],"cwes":["CWE-841","CWE-166"],"updated_at":"2026-11-02T14:20:14.302133Z"}],"euvd":[{"id":"EUVD-2026-19948","description":"Botan is a C++ cryptography library. Prior to version 3.11.1, the TLS 1.3 implementation allowed ApplicationData records to be processed prior to the Finished message being received. A server which is attempting to enforce client authentication via certificates can by bypassed by a client which entirely omits Certificate, CertificateVerify, and the Finished message and instead sends application data records. This vulnerability is fixed in 3.11.1.","status":"published","published":"2026-04-07T21:13:49Z","modified":"2026-07-15T01:04:16Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T18:19:56.47701Z"}],"nvd":[{"id":"CVE-2026-34582","description":"Botan is a C++ cryptography library. Prior to version 3.11.1, the TLS 1.3 implementation allowed ApplicationData records to be processed prior to the Finished message being received. A server which is attempting to enforce client authentication via certificates can by bypassed by a client which entirely omits Certificate, CertificateVerify, and the Finished message and instead sends application data records. This vulnerability is fixed in 3.11.1.","status":"published","published":"2026-04-07T22:16:22.81Z","modified":"2026-07-24T22:10:00.14Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/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":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical","assessor":"primary"},{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical","assessor":"secondary"}],"cwes":["CWE-841","CWE-166"],"updated_at":"2026-11-02T14:12:13.535987Z"}],"osv":[{"id":"ALPINE-CVE-2026-34582","description":"Botan is a C++ cryptography library. Prior to version 3.11.1, the TLS 1.3 implementation allowed ApplicationData records to be processed prior to the Finished message being received. A server which is attempting to enforce client authentication via certificates can by bypassed by a client which entirely omits Certificate, CertificateVerify, and the Finished message and instead sends application data records. This vulnerability is fixed in 3.11.1.","status":"published","published":"2026-04-07T22:16:22.81Z","modified":"2026-10-01T02:17:49.25887495Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical"}],"updated_at":"2026-11-02T15:27:50.269992Z"},{"id":"CVE-2026-34582","title":"Botan has a TLS 1.3 certificate authentication bypass","description":"Botan is a C++ cryptography library. Prior to version 3.11.1, the TLS 1.3 implementation allowed ApplicationData records to be processed prior to the Finished message being received. A server which is attempting to enforce client authentication via certificates can by bypassed by a client which entirely omits Certificate, CertificateVerify, and the Finished message and instead sends application data records. This vulnerability is fixed in 3.11.1.","status":"published","published":"2026-04-07T21:13:49.281Z","modified":"2026-10-28T02:31:13.197465354Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N","level":"high"}],"cwes":["CWE-841"],"updated_at":"2026-11-02T15:45:02.247031Z"},{"id":"DEBIAN-CVE-2026-34582","description":"Botan is a C++ cryptography library. Prior to version 3.11.1, the TLS 1.3 implementation allowed ApplicationData records to be processed prior to the Finished message being received. A server which is attempting to enforce client authentication via certificates can by bypassed by a client which entirely omits Certificate, CertificateVerify, and the Finished message and instead sends application data records. This vulnerability is fixed in 3.11.1.","status":"published","published":"2026-04-07T22:16:22.81Z","modified":"2026-10-01T03:03:10.576190284Z","cvss":[{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical"}],"updated_at":"2026-11-02T15:45:54.587575Z"},{"id":"UBUNTU-CVE-2026-34582","description":"Botan is a C++ cryptography library. Prior to version 3.11.1, the TLS 1.3 implementation allowed ApplicationData records to be processed prior to the Finished message being received. A server which is attempting to enforce client authentication via certificates can by bypassed by a client which entirely omits Certificate, CertificateVerify, and the Finished message and instead sends application data records. This vulnerability is fixed in 3.11.1.","status":"published","published":"2026-04-07T22:16:00Z","modified":"2026-10-17T12:58:11.837802015Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N","level":"high"},{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical"},{"version":"3.1","score":9.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","level":"critical"}],"updated_at":"2026-11-02T16:56:16.036833Z"},{"id":"AZL-81942","title":"CVE-2026-34582 affecting package botan2 2.14.0-2","description":"Botan is a C++ cryptography library. Prior to version 3.11.1, the TLS 1.3 implementation allowed ApplicationData records to be processed prior to the Finished message being received. A server which is attempting to enforce client authentication via certificates can by bypassed by a client which entirely omits Certificate, CertificateVerify, and the Finished message and instead sends application data records. This vulnerability is fixed in 3.11.1.","status":"published","published":"2026-04-07T22:16:22Z","modified":"2026-11-05T05:36:30Z","updated_at":"2026-11-05T16:41:24.988217Z"},{"id":"openSUSE-SU-2026:20528-1","title":"Security update for Botan","description":"This update for Botan fixes the following issues:\n\n- CVE-2026-34582: Fixed a client authentication bypass in TLS 1.3 implementation (bsc#1261880)\n","status":"published","published":"2026-04-14T11:18:14Z","modified":"2026-04-22T18:24:46.433586Z","updated_at":"2026-11-02T16:58:41.463445Z"}]}}