UnratedFix available
Fix CVE(s): CVE-2026-43964
Type: advisorySources: OSV
* SECURITY UPDATE: buffer over-read when an enhanced status code is not followed by any text - debian/patches/CVE-2026-43964.patch: stop dsn_split() advancing the cursor past the terminating NUL when the status code occupies the whole string (upstream 4992c82ad9, postfix-3.8.16). - CVE-2026-43964 * Recognise Linux 5 and 6 build hosts - debian/patches/support-linux-5-and-6-build-hosts.patch: postfix 3.3.0 predates Linux 5, so makedefs aborted with "Unknown system type" on the EL9 (5.14) build nodes before compiling anything. Widen the case list and add LINUX5/LINUX6 to the existing LINUX2/3/4 sys_defs.h group, so the defines match a Linux 4 host exactly.
- Products
- postfix, postfix-cdb, postfix-doc, postfix-ldap, postfix-lmdb, postfix-mysql, postfix-pcre, postfix-pgsql, postfix-sqlite
- Affected versions
- Not specified
- Fixed versions
- 3.3.0-1ubuntu0.4+tuxcare.els1
- CVEs
- CVE-2026-43964
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 11:42 UTC · Revision 1
Source evidence
* SECURITY UPDATE: buffer over-read when an enhanced status code is not followed by any text - debian/patches/CVE-2026-43964.patch: stop dsn_split() advancing the cursor past the terminating NUL when the status code occupies the whole string (upstream 4992c82ad9, postfix-3.8.16). - CVE-2026-43964 * Recognise Linux 5 and 6 build hosts - debian/patches/support-linux-5-and-6-build-hosts.patch: postfix 3.3.0 predates Linux 5, so makedefs aborted with "Unknown system type" on the EL9 (5.14) build nodes before compiling anything. Widen the case list and add LINUX5/LINUX6 to the existing LINUX2/3/4 sys_defs.h group, so the defines match a Linux 4 host exactly.
osv:CLSA-2026-1788261251
postfix
Fixed versions: 3.3.0-1ubuntu0.4+tuxcare.els1
postfix-cdb
Fixed versions: 3.3.0-1ubuntu0.4+tuxcare.els1
postfix-doc
Fixed versions: 3.3.0-1ubuntu0.4+tuxcare.els1
postfix-ldap
Fixed versions: 3.3.0-1ubuntu0.4+tuxcare.els1
postfix-lmdb
Fixed versions: 3.3.0-1ubuntu0.4+tuxcare.els1
postfix-mysql
Fixed versions: 3.3.0-1ubuntu0.4+tuxcare.els1
postfix-pcre
Fixed versions: 3.3.0-1ubuntu0.4+tuxcare.els1
postfix-pgsql
Fixed versions: 3.3.0-1ubuntu0.4+tuxcare.els1
postfix-sqlite
Fixed versions: 3.3.0-1ubuntu0.4+tuxcare.els1
Complete source record
{
"id": "4bb749ddbdec4c906bbfe9bde3e821804caab557f2b286477a2e7da295440537",
"url": "https://osv.dev/vulnerability/CLSA-2026-1788261251",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Fix CVE(s): CVE-2026-43964",
"summary": "* SECURITY UPDATE: buffer over-read when an enhanced status code is not followed by any text - debian/patches/CVE-2026-43964.patch: stop dsn_split() advancing the cursor past the terminating NUL when the status code occupies the whole string (upstream 4992c82ad9, postfix-3.8.16). - CVE-2026-43964 * Recognise Linux 5 and 6 build hosts - debian/patches/support-linux-5-and-6-build-hosts.patch: postfix 3.3.0 predates Linux 5, so makedefs aborted with \"Unknown system type\" on the EL9 (5.14) build nodes before compiling anything. Widen the case list and add LINUX5/LINUX6 to the existing LINUX2/3/4 sys_defs.h group, so the defines match a Linux 4 host exactly.",
"evidence": "osv:CLSA-2026-1788261251",
"products": [
{
"name": {
"value": "postfix",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "3.3.0-1ubuntu0.4+tuxcare.els1",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "postfix-cdb",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "3.3.0-1ubuntu0.4+tuxcare.els1",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "postfix-doc",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "3.3.0-1ubuntu0.4+tuxcare.els1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "postfix-ldap",
"evidence": "/affected/3/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "3.3.0-1ubuntu0.4+tuxcare.els1",
"evidence": "/affected/3/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "postfix-lmdb",
"evidence": "/affected/4/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "3.3.0-1ubuntu0.4+tuxcare.els1",
"evidence": "/affected/4/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "postfix-mysql",
"evidence": "/affected/5/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "3.3.0-1ubuntu0.4+tuxcare.els1",
"evidence": "/affected/5/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "postfix-pcre",
"evidence": "/affected/6/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "3.3.0-1ubuntu0.4+tuxcare.els1",
"evidence": "/affected/6/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "postfix-pgsql",
"evidence": "/affected/7/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "3.3.0-1ubuntu0.4+tuxcare.els1",
"evidence": "/affected/7/ranges"
}
],
"affected_versions": []
},
{
"name": {
"value": "postfix-sqlite",
"evidence": "/affected/8/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "3.3.0-1ubuntu0.4+tuxcare.els1",
"evidence": "/affected/8/ranges"
}
],
"affected_versions": []
}
],
"severity": "unknown",
"structured": {
"id": "CLSA-2026-1788261251",
"aliases": [
"CLSA-2026-1788261251"
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.3.0-1ubuntu0.4+tuxcare.els1"
}
]
}
],
"package": {
"name": "postfix",
"purl": "pkg:deb/tuxcare/postfix?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788261251.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.3.0-1ubuntu0.4+tuxcare.els1"
}
]
}
],
"package": {
"name": "postfix-cdb",
"purl": "pkg:deb/tuxcare/postfix-cdb?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788261251.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.3.0-1ubuntu0.4+tuxcare.els1"
}
]
}
],
"package": {
"name": "postfix-doc",
"purl": "pkg:deb/tuxcare/postfix-doc?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788261251.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.3.0-1ubuntu0.4+tuxcare.els1"
}
]
}
],
"package": {
"name": "postfix-ldap",
"purl": "pkg:deb/tuxcare/postfix-ldap?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788261251.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.3.0-1ubuntu0.4+tuxcare.els1"
}
]
}
],
"package": {
"name": "postfix-lmdb",
"purl": "pkg:deb/tuxcare/postfix-lmdb?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788261251.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.3.0-1ubuntu0.4+tuxcare.els1"
}
]
}
],
"package": {
"name": "postfix-mysql",
"purl": "pkg:deb/tuxcare/postfix-mysql?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788261251.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.3.0-1ubuntu0.4+tuxcare.els1"
}
]
}
],
"package": {
"name": "postfix-pcre",
"purl": "pkg:deb/tuxcare/postfix-pcre?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788261251.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.3.0-1ubuntu0.4+tuxcare.els1"
}
]
}
],
"package": {
"name": "postfix-pgsql",
"purl": "pkg:deb/tuxcare/postfix-pgsql?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788261251.json"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.3.0-1ubuntu0.4+tuxcare.els1"
}
]
}
],
"package": {
"name": "postfix-sqlite",
"purl": "pkg:deb/tuxcare/postfix-sqlite?distro=ubuntu-18.04",
"ecosystem": "TuxCare:Ubuntu:18.04"
},
"database_specific": {
"source": "https://github.com/cloudlinux/tuxcare-osv/tree/main/data/els_os/ubuntu18.04els/CLSA-2026-1788261251.json"
}
}
],
"modified": "2026-10-26T09:32:03.920649219Z",
"provider": "osv",
"upstream": [
"CVE-2026-43964"
],
"references": [
"https://errata.tuxcare.com/els_os/ubuntu18.04els/CLSA-2026-1788261251.html",
"https://nvd.nist.gov/vuln/detail/CVE-2026-43964"
]
},
"related_cves": [
{
"value": "CVE-2026-43964",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": null
},
"source_id": "core-osv",
"document_id": 449562,
"published_at": "2026-09-01T11:14:21+00:00"
}