CVE-2026-43964

Postfix before 3.8.16, 3.9 before 3.9.10, and 3.10 before 3.10.9 sometimes allows a buffer over-read and process crash via an enhanced status code that lacks text after the third number.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://www.mail-archive.com/postfix-announce@postfix.org/msg00110.html	Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2026/05/04/30	Mailing List Third Party Advisory
https://access.redhat.com/errata/RHSA-2026:25930
https://access.redhat.com/errata/RHSA-2026:25932
https://access.redhat.com/errata/RHSA-2026:26205
https://access.redhat.com/errata/RHSA-2026:50963
https://access.redhat.com/errata/RHSA-2026:50964
https://access.redhat.com/errata/RHSA-2026:51034
https://access.redhat.com/errata/RHSA-2026:51436
https://access.redhat.com/errata/RHSA-2026:57174
https://access.redhat.com/security/cve/CVE-2026-43964
https://bugzilla.redhat.com/show_bug.cgi?id=2466488
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43964.json

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:postfix:postfix::::::::
	cpe:2.3:a:postfix:postfix::::::::
	cpe:2.3:a:postfix:postfix::::::::

History

No history.

Information

Published : 2026-05-04 19:16

Updated : 2026-08-20 13:18

NVD link : CVE-2026-43964

Mitre link : CVE-2026-43964

CVE.ORG link : CVE-2026-43964

JSON object : View

Products Affected

postfix

postfix

CWE

CWE-193

Off-by-one Error

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{"url": "http://www.openwall.com/lists/oss-security/2026/05/04/30", "tags": ["Mailing List", "Third Party Advisory"], "source": "af854a3a-2127-422b-91ae-364da2661108"}, {"url": "https://access.redhat.com/errata/RHSA-2026:25930", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:25932", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:26205", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:50963", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:50964", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:51034", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:51436", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:57174", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/security/cve/CVE-2026-43964", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2466488", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43964.json", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Secondary", "source": "cve@mitre.org", "description": [{"lang": "en", "value": "CWE-193"}]}, {"type": "Secondary", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "description": [{"lang": "en", "value": "CWE-193"}]}], "descriptions": [{"lang": "en", "value": "Postfix before 3.8.16, 3.9 before 3.9.10, and 3.10 before 3.10.9 sometimes allows a buffer over-read and process crash via an enhanced status code that lacks text after the third number."}], "lastModified": "2026-08-20T13:18:37.960", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:postfix:postfix:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "439B2155-5F30-42FD-B57A-32B7AC32E2A1", "versionEndExcluding": "3.8.16"}, {"criteria": "cpe:2.3:a:postfix:postfix:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4AE4398A-5217-408E-BF9B-D3A9ACC0E6C6", "versionEndExcluding": "3.9.10", "versionStartIncluding": "3.9.0"}, {"criteria": "cpe:2.3:a:postfix:postfix:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0A9CB1E4-A91E-4EC9-9E4E-7F41679EEF13", "versionEndExcluding": "3.10.9", "versionStartIncluding": "3.10.0"}], "operator": "OR"}]}], "sourceIdentifier": "cve@mitre.org"}