CVE-2026-43964

LOW

3.7

CVSS v3

Description

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.

CWE-193

How to fix

Remediation Available

postfixDebian

Fixed in:3.10.10-0+deb13u1CVE-2026-43964

Fixed in:3.11.2-1CVE-2026-43964

postfixRed Hat / RHEL

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

postfixRocky

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

postfix-cdbRed Hat / RHEL

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

postfix-cdbRocky

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

postfix-cdb-debuginfoRed Hat / RHEL

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

postfix-cdb-debuginfoRocky

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

postfix-debuginfoRocky

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

postfix-debuginfoRed Hat / RHEL

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

postfix-debugsourceRocky

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

postfix-debugsourceRed Hat / RHEL

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

postfix-ldapRocky

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

postfix-ldapRed Hat / RHEL

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

postfix-ldap-debuginfoRed Hat / RHEL

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

postfix-ldap-debuginfoRocky

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

postfix-lmdbRocky

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

postfix-lmdbRed Hat / RHEL

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

postfix-lmdb-debuginfoRocky

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

postfix-lmdb-debuginfoRed Hat / RHEL

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

postfix-mysqlRed Hat / RHEL

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

postfix-mysqlRocky

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

postfix-mysql-debuginfoRocky

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

postfix-mysql-debuginfoRed Hat / RHEL

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

postfix-pcreRocky

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

postfix-pcreRed Hat / RHEL

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

postfix-pcre-debuginfoRed Hat / RHEL

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

postfix-pcre-debuginfoRocky

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

postfix-perl-scriptsRocky

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

postfix-perl-scriptsRed Hat / RHEL

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

postfix-pgsqlRed Hat / RHEL

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

Fixed in:2:3.8.5-10.el10_2RHSA-2026:25930

Fixed in:2:3.8.5-8.el10_0.1RHSA-2026:51436

This vulnerability affects an unusually large number of packages. The highest-confidence fixes are shown above; the full list is longer. Check the referenced advisories for complete coverage.

TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityHigh

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityNone

IntegrityNone

AvailabilityLow

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

Exploit Intelligence

0.51%probability of exploitation in 30 days

41stpercentile

Moderate risk: more likely to be exploited than 41% of all known CVEs.

References

Third-Party Advisory2

Other references11

Related Vulnerabilities

Other CWE-193 vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2021-3156	High	7.8	100%	KEV	Fix
CVE-2003-0466	Critical	9.8	78%	-	-
CVE-2023-44444	High	7.8	56%	-	Fix
CVE-2021-23017	High	7.7	53%	-	Fix
CVE-2023-28709	High	7.5	50%	-	Fix
CVE-2018-8828	Critical	9.8	30%	-	Fix

Common questions

How do I fix CVE-2026-43964?

Published advisories record a fix for 40 affected products. The "How to fix" section on this page lists the fixed version and source advisory for each one, so apply the entry matching what you actually run.

Is CVE-2026-43964 being actively exploited?

Not that we know of. CVE-2026-43964 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.51% is the estimated probability that it will be exploited in the next 30 days. That is higher than 41% of all scored CVEs.

How severe is CVE-2026-43964?

CVE-2026-43964 has a CVSS v3 base score of 3.7, rated low. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

What does CVE-2026-43964 affect?

Published advisories record a fix for postfix (Debian), postfix (Red Hat / RHEL), postfix (Rocky), postfix-cdb (Red Hat / RHEL), and 36 more. Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.

Embed a live status badge for CVE-2026-43964

Markdown

[![CVE-2026-43964](https://tridentstack.com/cve/badge/CVE-2026-43964.svg)](https://tridentstack.com/cve/CVE-2026-43964)

HTML

<a href="https://tridentstack.com/cve/CVE-2026-43964"><img src="https://tridentstack.com/cve/badge/CVE-2026-43964.svg" alt="CVE-2026-43964"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

See how it works Start freeThis CVE lookup is free and always will be.

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-08-20.