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.

The remote RockyLinux 10 host has packages installed that are affected by a vulnerability as referenced in the RLSA-2026:25930 advisory.

    * postfix: buffer over-read via malformed enhanced status code (CVE-2026-43964)

Tenable has extracted the preceding description block directly from the RockyLinux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote RockyLinux 9 host has packages installed that are affected by a vulnerability as referenced in the RLSA-2026:26205 advisory.

    * postfix: buffer over-read via malformed enhanced status code (CVE-2026-43964)

Tenable has extracted the preceding description block directly from the RockyLinux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote MiracleLinux 8 host has packages installed that are affected by a vulnerability as referenced in the AXSA:2026-789:01 advisory.

    * postfix: buffer over-read via malformed enhanced status code (CVE-2026-43964)

Tenable has extracted the preceding description block directly from the MiracleLinux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote RockyLinux 8 host has packages installed that are affected by a vulnerability as referenced in the RLSA-2026:25932 advisory.

    * postfix: buffer over-read via malformed enhanced status code (CVE-2026-43964)

Tenable has extracted the preceding description block directly from the RockyLinux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Redhat Enterprise Linux 9 host has packages installed that are affected by a vulnerability as referenced in the RHSA-2026:26205 advisory.

    The postfix packages provide a Mail Transport Agent (MTA), which supports protocols like LDAP, SMTP AUTH     (SASL), and TLS.

    Security Fix(es):

    * postfix: buffer over-read via malformed enhanced status code (CVE-2026-43964)

    For 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.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Oracle Linux 8 host has packages installed that are affected by a vulnerability as referenced in the ELSA-2026-25932 advisory.

    [2:3.5.8-8]
    - Fix for CVE-2026-43964: buffer over-read via malformed enhanced status code.
      Resolves: RHEL-176548

Tenable has extracted the preceding description block directly from the Oracle Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote AlmaLinux 8 host has packages installed that are affected by a vulnerability as referenced in the ALSA-2026:25932 advisory.

    * postfix: buffer over-read via malformed enhanced status code (CVE-2026-43964)

Tenable has extracted the preceding description block directly from the AlmaLinux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote AlmaLinux 10 host has packages installed that are affected by a vulnerability as referenced in the ALSA-2026:25930 advisory.

    * postfix: buffer over-read via malformed enhanced status code (CVE-2026-43964)

Tenable has extracted the preceding description block directly from the AlmaLinux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Redhat Enterprise Linux 8 host has packages installed that are affected by a vulnerability as referenced in the RHSA-2026:25932 advisory.

    The postfix packages provide a Mail Transport Agent (MTA), which supports protocols like LDAP, SMTP AUTH     (SASL), and TLS.

    Security Fix(es):

    * postfix: buffer over-read via malformed enhanced status code (CVE-2026-43964)

    For 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.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Redhat Enterprise Linux 10 host has packages installed that are affected by a vulnerability as referenced in the RHSA-2026:25930 advisory.

    The postfix packages provide a Mail Transport Agent (MTA), which supports protocols like LDAP, SMTP AUTH     (SASL), and TLS.

    Security Fix(es):

    * postfix: buffer over-read via malformed enhanced status code (CVE-2026-43964)

    For 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.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Fedora 44 host has a package installed that is affected by a vulnerability as referenced in the FEDORA-2026-5cf8cc5f32 advisory.

    This is an update fixing CVE-2026-43964.

Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Fedora 43 host has a package installed that is affected by a vulnerability as referenced in the FEDORA-2026-e9fc21d7e2 advisory.

    This is an update fixing CVE-2026-43964.

Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The remote Ubuntu 22.04 LTS / 24.04 LTS / 25.10 / 26.04 LTS host has packages installed that are affected by a vulnerability as referenced in the USN-8253-1 advisory.

    Kamil Frankowicz discovered that Postfix incorrectly handled certain enhanced status codes. A remote     attacker could possibly use this issue to cause Postfix to crash, resulting in a denial of service.

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - 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. (CVE-2026-43964)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Severity
321669	RockyLinux 10 : postfix (RLSA-2026:25930)	Nessus	Rocky Linux Local Security Checks	high
321392	RockyLinux 9 : postfix (RLSA-2026:26205)	Nessus	Rocky Linux Local Security Checks	high
321348	MiracleLinux 8 : postfix-3.5.8-8.el8_10 (AXSA:2026-789:01)	Nessus	Miracle Linux Local Security Checks	high
321334	RockyLinux 8 : postfix (RLSA-2026:25932)	Nessus	Rocky Linux Local Security Checks	high
321268	RHEL 9 : postfix (RHSA-2026:26205)	Nessus	Red Hat Local Security Checks	high
321218	Oracle Linux 8 : post (ELSA-2026-25932)	Nessus	Oracle Linux Local Security Checks	high
321213	AlmaLinux 8 : postfix (ALSA-2026:25932)	Nessus	Alma Linux Local Security Checks	high
321114	AlmaLinux 10 : postfix (ALSA-2026:25930)	Nessus	Alma Linux Local Security Checks	high
321110	RHEL 8 : postfix (RHSA-2026:25932)	Nessus	Red Hat Local Security Checks	high
321097	RHEL 10 : postfix (RHSA-2026:25930)	Nessus	Red Hat Local Security Checks	high
318216	Fedora 44 : postfix (2026-5cf8cc5f32)	Nessus	Fedora Local Security Checks	high
318197	Fedora 43 : postfix (2026-e9fc21d7e2)	Nessus	Fedora Local Security Checks	high
314221	Ubuntu 22.04 LTS / 24.04 LTS / 25.10 / 26.04 LTS : Postfix vulnerability (USN-8253-1)	Nessus	Ubuntu Local Security Checks	high
312107	Linux Distros Unpatched Vulnerability : CVE-2026-43964	Nessus	Misc.	high

Detections

Analytics

CVE-2026-43964

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Tenable Plugins

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