CVE-2026-43916
pam_authnft: Heap buffer overflow in NETLINK_SOCK_DIAG reply walker
Description
pam_authnft is a PAM session module binding nftables firewall rules to authenticated sessions via cgroupv2 inodes. Prior to 0.2.0-alpha, a heap buffer over-read in peer_lookup_tcp (src/peer_lookup.c:134, prior to the fix) allowed a crafted NETLINK_SOCK_DIAG reply to slip past the message-size check, then dereference past the end of the allocation. This vulnerability is fixed in 0.2.0-alpha.
INFO
Published Date :
May 12, 2026, 2:17 p.m.
Last Modified :
Oct. 26, 2026, 6:10 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update pam_authnft to version 0.2.0-alpha.
- Ensure firewall rules are correctly bound to authenticated sessions.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-43916.
| URL | Resource |
|---|---|
| https://github.com/identd-ng/pam_authnft/pull/10 | |
| https://github.com/identd-ng/pam_authnft/security/advisories/GHSA-5jj5-hm34-78vh |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-43916 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-43916
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-43916 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-43916 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Translated by [email protected]
Oct. 26, 2026
Action Type Old Value New Value Added Translation Title: pam_authnft de identd-ng, Description: pam_authnft es un módulo de sesión PAM que vincula reglas de cortafuegos de nftables a sesiones autenticadas a través de inodos cgroupv2. Antes de la versión 0.2.0-alpha, una lectura excesiva del búfer de la pila en peer_lookup_tcp (src/peer_lookup.c:134, antes de la corrección) permitía que una respuesta NETLINK_SOCK_DIAG manipulada eludiera la comprobación del tamaño del mensaje, y luego desreferenciara más allá del final de la asignación. Esta vulnerabilidad está corregida en la versión 0.2.0-alpha. -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'identd-ng', 'product': 'pam_authnft', 'versions': [{'status': 'affected', 'version': '< 0.2.0-alpha'}]}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-43916', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-05-13T14:32:22.591683Z'} -
New CVE Received by [email protected]
May. 12, 2026
Action Type Old Value New Value Added Description pam_authnft is a PAM session module binding nftables firewall rules to authenticated sessions via cgroupv2 inodes. Prior to 0.2.0-alpha, a heap buffer over-read in peer_lookup_tcp (src/peer_lookup.c:134, prior to the fix) allowed a crafted NETLINK_SOCK_DIAG reply to slip past the message-size check, then dereference past the end of the allocation. This vulnerability is fixed in 0.2.0-alpha. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-125 Added CWE CWE-191 Added Reference https://github.com/identd-ng/pam_authnft/pull/10 Added Reference https://github.com/identd-ng/pam_authnft/security/advisories/GHSA-5jj5-hm34-78vh