CVE-2026-31418: netfilter: ipset: drop logically empty buckets in mtype_del
In the Linux kernel, the following vulnerability has been resolved:
netfilter: ipset: drop logically empty buckets in mtypedel
mtypedel() counts empty slots below n->pos in k, but it only drops the bucket when both n->pos and k are zero. This misses buckets whose live entries have all been removed while n->pos still points past deleted slots.
Treat a bucket as empty when all positions below n->pos are unused and release it directly instead of shrinking it further.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-31418?
CVE-2026-31418 has a moderate severity rating due to its potential impact on the Linux kernel's netfilter ipset functionality.
How do I fix CVE-2026-31418?
To fix CVE-2026-31418, update to a patched version of the Linux kernel that addresses this vulnerability.
What are the potential impacts of CVE-2026-31418?
The potential impacts of CVE-2026-31418 include unexpected behavior in ipset operations, which could lead to denial of service scenarios.
Which Linux kernel versions are affected by CVE-2026-31418?
CVE-2026-31418 affects multiple versions of the Linux kernel that utilize netfilter ipset before being patched.
Is CVE-2026-31418 being actively exploited?
As of now, there is no public evidence indicating that CVE-2026-31418 is being actively exploited in the wild.