CVE-2026-99131

Status: UPDATED  |  Advisory ID: CVE-2026-99131

Key Details

Affected Products, Subsystems & Sectors

What to Know

In the Linux kernel, the following vulnerability has been resolved:

xfs: fix capability check in xfs

An user reported a bug where he managed to evade group's quota

by changing a file's gid to a different group id the same user

belonged to, even though quotas were enforced on both gids and the

file's size was big enough to exceed the quota's hardlimit.

Commit eba0549bc7d1 replaced a capable() call by a

has_capability_noaudit() to prevent unnecessary selinux audit messages.

Turns out that both calls have slightly different semantics even though

their documentation seems similar. Where in a nutshell:

capable() - Tests the task's effective credentials

has_ns_capability_noaudit() - Tests the task's real credentials

This most of the time has no practical difference but in some cases like

changing attrs (specifically group id in this case) through a NFS client

this will allow the quota code to use XFS_QMOPT_FORCE_RES, effectively

bypassing quota accounting checks.

Using instead ns_capable_noaudit() should fix this issue and prevent

selinux audit messages.

This also fix the remaining calls to has_capability_noaudit() (NVD)

What to Do

Monitor Linux's web page for any future patch releases.

References