CVE-2026-43916 pam_authnft: Heap buffer overflow in NETLINK_SOCK_DIAG reply walker
A heap buffer over-read in pam_authnft allows attackers to cause denial of service or disclose memory via crafted NETLINK_SOCK_DIAG replies.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-43916?
CVE-2026-43916 is a high-severity memory corruption vulnerability in identd-ng pam_authnft, published on 12 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Which versions are affected by CVE-2026-43916?
How do I fix CVE-2026-43916?
No fix has been published for CVE-2026-43916 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-43916 being exploited?
There is no known exploitation of CVE-2026-43916 in the wild and no public exploit code.
Sources
Also known as GHSA-5jj5-hm34-78vh.