{"id":"CVE-2026-77205","aliases":["ALPINE-CVE-2026-77205","ALSA-2026:89923","DEBIAN-CVE-2026-77205","EUVD-2026-100747","GHSA-7m29-c28j-rg7h","RLSA-2026:89923","UBUNTU-CVE-2026-77205"],"status":"published","title":"Denial of Service via sending bogus X.509 certificates","description":"Libreswan in FIPS mode has a vulnerability where badly formed received certificates are rejected, but not deleted from the NSS cache. As a result, any real certificates with the same serial number are rejected as well. This can be abused to lock out legitimate peers from connecting. The add_decoded_cert() function missed a call to CERT_DestroyCertificate() due to an incorrect fix for CVE-2026-14957. Sending bogus certificates with new serial numbers could prevent the real certificates with those serial numbers from connecting until the service has restarted.","severity":{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"low","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00183,"percentile":0.0796,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-772"],"published":"2026-10-13T21:28:03Z","modified":"2026-11-03T06:32:57Z","fixes":[{"ecosystem":"Alpine:v3.23","package":"libreswan","fixed_in":["5.3.3-r0"],"sources":["osv"]},{"ecosystem":"Alpine:v3.24","package":"libreswan","fixed_in":["5.3.3-r0"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Alpine:v3.23","package":"libreswan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.3.3-r0"}]}]},{"source":"osv","ecosystem":"Alpine:v3.24","package":"libreswan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.3.3-r0"}]}]},{"source":"osv","ecosystem":"AlmaLinux:10","package":"libreswan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.3.3-1.el10_2"}]}],"bundled":3},{"source":"osv","ecosystem":"AlmaLinux:10","package":"libreswan-minimal","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.3.3-1.el10_2"}]}],"bundled":3},{"source":"osv","ecosystem":"Debian:14","package":"libreswan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.2-2.2","5.2-2.3","5.2-2.4","5.2-2.5"]},{"source":"osv","ecosystem":"Rocky Linux:10","package":"libreswan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:5.3.3-1.el10_2"}]}],"bundled":3},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"libreswan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.20-7build1","3.21-2","3.22-1","3.22-2","3.22-3","3.22-4","3.23-1","3.23-4"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"libreswan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.29-2","3.29-2build1"]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"libreswan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.32-3ubuntu3"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"libreswan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.11-1ubuntu1","4.12-1ubuntu1","4.14-1ubuntu1","4.14-1ubuntu2"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"libreswan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.2-2.2ubuntu2"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"libreswan","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.2-2.2ubuntu1","5.2-2.2ubuntu2"]}],"products":[{"vendor":"the libreswan project","product":"libreswan"},{"vendor":"the libreswan project (www.libreswan.org)","product":"libreswan"}],"references":[{"url":"https://libreswan.org/security/CVE-2026-77205/CVE-2026-77205.txt","tags":["vendor-advisory","report"]},{"url":"https://libreswan.org/security/CVE-2026-77205/","tags":["patch","report"]},{"url":"https://libreswan.org/security/CVE-2026-14957/CVE-2026-14957.txt","tags":["related","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-77205"},{"url":"https://libreswan.org/security/CVE-2026-77205"},{"url":"https://github.com/advisories/GHSA-7m29-c28j-rg7h"},{"url":"https://security.alpinelinux.org/vuln/CVE-2026-77205","tags":["advisory"]},{"url":"https://access.redhat.com/errata/RHSA-2026:89923","tags":["advisory"]},{"url":"https://access.redhat.com/security/cve/CVE-2026-77205","tags":["report"]},{"url":"https://access.redhat.com/security/cve/CVE-2026-77207","tags":["report"]},{"url":"https://access.redhat.com/security/cve/CVE-2026-94453","tags":["report"]},{"url":"https://bugzilla.redhat.com/2550254","tags":["report"]},{"url":"https://bugzilla.redhat.com/2550255","tags":["report"]},{"url":"https://bugzilla.redhat.com/2550258","tags":["report"]},{"url":"https://errata.almalinux.org/10/ALSA-2026-89923.html","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-77205","tags":["advisory"]},{"url":"https://errata.rockylinux.org/RLSA-2026:89923","tags":["advisory"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2550254","tags":["report"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2550255","tags":["report"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2550258","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2026-77205","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-77205","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-77205","title":"Denial of Service via sending bogus X.509 certificates","description":"Libreswan in FIPS mode has a vulnerability where badly formed received certificates are rejected, but not deleted from the NSS cache. As a result, any real certificates with the same serial number are rejected as well. This can be abused to lock out legitimate peers from connecting. The add_decoded_cert() function missed a call to CERT_DestroyCertificate() due to an incorrect fix for CVE-2026-14957. Sending bogus certificates with new serial numbers could prevent the real certificates with those serial numbers from connecting until the service has restarted.","status":"published","published":"2026-10-13T21:28:03.39Z","modified":"2026-10-16T15:31:54.457Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"low","assessor":"cna"}],"cwes":["CWE-772"],"updated_at":"2026-11-02T14:20:16.072351Z"}],"euvd":[{"id":"EUVD-2026-100747","description":"Libreswan in FIPS mode has a vulnerability where badly formed received certificates are rejected, but not deleted from the NSS cache. As a result, any real certificates with the same serial number are rejected as well. This can be abused to lock out legitimate peers from connecting. The add_decoded_cert() function missed a call to CERT_DestroyCertificate() due to an incorrect fix for CVE-2026-14957. Sending bogus certificates with new serial numbers could prevent the real certificates with those serial numbers from connecting until the service has restarted.","status":"published","published":"2026-10-13T21:28:03Z","modified":"2026-10-16T15:31:54Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"low"}],"updated_at":"2026-11-02T17:00:05.229655Z"}],"ghsa":[{"id":"GHSA-7m29-c28j-rg7h","title":"Libreswan in FIPS mode has a vulnerability where badly formed received certificates are rejected,...","description":"Libreswan in FIPS mode has a vulnerability where badly formed received certificates are rejected, but not deleted from the NSS cache. As a result, any real certificates with the same serial number are rejected as well. This can be abused to lock out legitimate peers from connecting. The add_decoded_cert() function missed a call to CERT_DestroyCertificate() due to an incorrect fix for CVE-2026-14957. Sending bogus certificates with new serial numbers could prevent the real certificates with those serial numbers from connecting until the service has restarted.","status":"published","published":"2026-10-14T00:31:47Z","modified":"2026-10-14T00:31:55Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"low"}],"cwes":["CWE-772"],"updated_at":"2026-11-02T15:13:22.12395Z"}],"nvd":[{"id":"CVE-2026-77205","description":"Libreswan in FIPS mode has a vulnerability where badly formed received certificates are rejected, but not deleted from the NSS cache. As a result, any real certificates with the same serial number are rejected as well. This can be abused to lock out legitimate peers from connecting. The add_decoded_cert() function missed a call to CERT_DestroyCertificate() due to an incorrect fix for CVE-2026-14957. Sending bogus certificates with new serial numbers could prevent the real certificates with those serial numbers from connecting until the service has restarted.","status":"published","published":"2026-10-13T22:18:24.577Z","modified":"2026-10-16T19:55:59.74Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"low","assessor":"secondary"}],"cwes":["CWE-772"],"updated_at":"2026-11-02T14:12:58.630796Z"}],"osv":[{"id":"ALPINE-CVE-2026-77205","description":"Libreswan in FIPS mode has a vulnerability where badly formed received certificates are rejected, but not deleted from the NSS cache. As a result, any real certificates with the same serial number are rejected as well. This can be abused to lock out legitimate peers from connecting. The add_decoded_cert() function missed a call to CERT_DestroyCertificate() due to an incorrect fix for CVE-2026-14957. Sending bogus certificates with new serial numbers could prevent the real certificates with those serial numbers from connecting until the service has restarted.","status":"published","published":"2026-10-13T22:18:24.577Z","modified":"2026-11-03T06:32:57.08392601Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"low"}],"updated_at":"2026-11-03T07:16:26.770911Z"},{"id":"DEBIAN-CVE-2026-77205","description":"Libreswan in FIPS mode has a vulnerability where badly formed received certificates are rejected, but not deleted from the NSS cache. As a result, any real certificates with the same serial number are rejected as well. This can be abused to lock out legitimate peers from connecting. The add_decoded_cert() function missed a call to CERT_DestroyCertificate() due to an incorrect fix for CVE-2026-14957. Sending bogus certificates with new serial numbers could prevent the real certificates with those serial numbers from connecting until the service has restarted.","status":"published","published":"2026-10-13T22:18:24.577Z","modified":"2026-10-23T17:47:24.957567609Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"low"}],"updated_at":"2026-11-02T15:46:03.502256Z"},{"id":"RLSA-2026:89923","title":"Important: libreswan security update","description":"Libreswan is an implementation of IPsec and IKE for Linux. IPsec is the Internet Protocol Security and uses strong cryptography to provide both authentication and encryption services. These services allow you to build secure tunnels through untrusted networks such as virtual private network (VPN).\n\nSecurity Fix(es):\n\n* libreswan: IKEv2 Use-After-Free bug when using IKE-over-TCP (CVE-2026-94453)\n\n* libreswan: Denial of Service via sending bogus X.509 certificates (CVE-2026-77205)\n\n* libreswan: Null Pointer Dereference in PKCS#7 bundle with no CERTS (CVE-2026-77207)\n\nFor more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.","status":"published","published":"2026-10-27T12:08:55.409043Z","modified":"2026-10-27T12:30:03.124689973Z","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":"2026-11-02T15:53:26.76659Z"},{"id":"UBUNTU-CVE-2026-77205","description":"Libreswan in FIPS mode has a vulnerability where badly formed received certificates are rejected, but not deleted from the NSS cache. As a result, any real certificates with the same serial number are rejected as well. This can be abused to lock out legitimate peers from connecting. The add_decoded_cert() function missed a call to CERT_DestroyCertificate() due to an incorrect fix for CVE-2026-14957. Sending bogus certificates with new serial numbers could prevent the real certificates with those serial numbers from connecting until the service has restarted.","status":"published","published":"2026-10-13T22:18:00Z","modified":"2026-10-17T13:01:07.367756344Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"low"}],"updated_at":"2026-11-02T16:57:13.483205Z"},{"id":"ALSA-2026:89923","title":"Important: libreswan security update","description":"Libreswan is an implementation of IPsec and IKE for Linux. IPsec is the Internet Protocol Security and uses strong cryptography to provide both authentication and encryption services. These services allow you to build secure tunnels through untrusted networks such as virtual private network (VPN).  \n\nSecurity Fix(es):  \n\n  * libreswan: IKEv2 Use-After-Free bug when using IKE-over-TCP (CVE-2026-94453)\n  * libreswan: Denial of Service via sending bogus X.509 certificates (CVE-2026-77205)\n  * libreswan: Null Pointer Dereference in PKCS#7 bundle with no CERTS (CVE-2026-77207)\n\n\nFor more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.\n","status":"published","published":"2026-10-26T00:00:00Z","modified":"2026-10-29T11:31:11.713049033Z","updated_at":"2026-11-02T15:27:57.367731Z"}]}}