{"id":"USN-8253-1","summary":"postfix vulnerability","details":"Kamil Frankowicz discovered that Postfix incorrectly handled certain\nenhanced status codes. A remote attacker could possibly use this issue to\ncause Postfix to crash, resulting in a denial of service.","modified":"2026-05-20T16:06:19.488135641Z","published":"2026-05-07T14:31:25Z","related":["UBUNTU-CVE-2026-43964"],"upstream":["UBUNTU-CVE-2026-43964"],"references":[{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8253-1"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-43964"}],"affected":[{"package":{"name":"postfix","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/postfix?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.6.4-1ubuntu1.4"}]}],"versions":["3.5.6-1ubuntu2","3.5.13-1ubuntu1","3.5.13-1ubuntu2","3.5.13-1ubuntu3","3.6.3-4ubuntu1","3.6.3-5ubuntu1","3.6.3-5ubuntu2","3.6.4-1ubuntu1","3.6.4-1ubuntu1.1","3.6.4-1ubuntu1.2","3.6.4-1ubuntu1.3"],"ecosystem_specific":{"binaries":[{"binary_name":"postfix","binary_version":"3.6.4-1ubuntu1.4"},{"binary_name":"postfix-cdb","binary_version":"3.6.4-1ubuntu1.4"},{"binary_name":"postfix-ldap","binary_version":"3.6.4-1ubuntu1.4"},{"binary_name":"postfix-lmdb","binary_version":"3.6.4-1ubuntu1.4"},{"binary_name":"postfix-mysql","binary_version":"3.6.4-1ubuntu1.4"},{"binary_name":"postfix-pcre","binary_version":"3.6.4-1ubuntu1.4"},{"binary_name":"postfix-pgsql","binary_version":"3.6.4-1ubuntu1.4"},{"binary_name":"postfix-sqlite","binary_version":"3.6.4-1ubuntu1.4"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8253-1.json","cves_map":{"cves":[{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2026-43964"}],"ecosystem":"Ubuntu:22.04:LTS"}}},{"package":{"name":"postfix","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/postfix?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.8.6-1ubuntu0.1"}]}],"versions":["3.8.1-2","3.8.2-1","3.8.3-1","3.8.4-1","3.8.5-1","3.8.6-1","3.8.6-1build1","3.8.6-1build2"],"ecosystem_specific":{"binaries":[{"binary_name":"postfix","binary_version":"3.8.6-1ubuntu0.1"},{"binary_name":"postfix-cdb","binary_version":"3.8.6-1ubuntu0.1"},{"binary_name":"postfix-ldap","binary_version":"3.8.6-1ubuntu0.1"},{"binary_name":"postfix-lmdb","binary_version":"3.8.6-1ubuntu0.1"},{"binary_name":"postfix-mysql","binary_version":"3.8.6-1ubuntu0.1"},{"binary_name":"postfix-pcre","binary_version":"3.8.6-1ubuntu0.1"},{"binary_name":"postfix-pgsql","binary_version":"3.8.6-1ubuntu0.1"},{"binary_name":"postfix-sqlite","binary_version":"3.8.6-1ubuntu0.1"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8253-1.json","cves_map":{"cves":[{"id":"CVE-2026-43964","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]}],"ecosystem":"Ubuntu:24.04:LTS"}}},{"package":{"name":"postfix","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/postfix?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.10.2-1ubuntu2.1"}]}],"versions":["3.9.1-10ubuntu1","3.10.2-1ubuntu1","3.10.2-1ubuntu2"],"ecosystem_specific":{"binaries":[{"binary_name":"postfix","binary_version":"3.10.2-1ubuntu2.1"},{"binary_name":"postfix-cdb","binary_version":"3.10.2-1ubuntu2.1"},{"binary_name":"postfix-ldap","binary_version":"3.10.2-1ubuntu2.1"},{"binary_name":"postfix-lmdb","binary_version":"3.10.2-1ubuntu2.1"},{"binary_name":"postfix-mongodb","binary_version":"3.10.2-1ubuntu2.1"},{"binary_name":"postfix-mysql","binary_version":"3.10.2-1ubuntu2.1"},{"binary_name":"postfix-pcre","binary_version":"3.10.2-1ubuntu2.1"},{"binary_name":"postfix-pgsql","binary_version":"3.10.2-1ubuntu2.1"},{"binary_name":"postfix-sqlite","binary_version":"3.10.2-1ubuntu2.1"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8253-1.json","cves_map":{"cves":[{"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}],"id":"CVE-2026-43964"}],"ecosystem":"Ubuntu:25.10"}}},{"package":{"name":"postfix","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/postfix?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.10.6-4ubuntu2.1"}]}],"versions":["3.10.2-1ubuntu2","3.10.2-1ubuntu3","3.10.6-1ubuntu1","3.10.6-4ubuntu1","3.10.6-4ubuntu2"],"ecosystem_specific":{"binaries":[{"binary_name":"postfix","binary_version":"3.10.6-4ubuntu2.1"},{"binary_name":"postfix-cdb","binary_version":"3.10.6-4ubuntu2.1"},{"binary_name":"postfix-ldap","binary_version":"3.10.6-4ubuntu2.1"},{"binary_name":"postfix-lmdb","binary_version":"3.10.6-4ubuntu2.1"},{"binary_name":"postfix-mongodb","binary_version":"3.10.6-4ubuntu2.1"},{"binary_name":"postfix-mysql","binary_version":"3.10.6-4ubuntu2.1"},{"binary_name":"postfix-pcre","binary_version":"3.10.6-4ubuntu2.1"},{"binary_name":"postfix-pgsql","binary_version":"3.10.6-4ubuntu2.1"},{"binary_name":"postfix-sqlite","binary_version":"3.10.6-4ubuntu2.1"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-8253-1.json","cves_map":{"cves":[{"id":"CVE-2026-43964","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]}],"ecosystem":"Ubuntu:26.04:LTS"}}}],"schema_version":"1.7.5"}