CVE-2026-31438

medium

Description

In the Linux kernel, the following vulnerability has been resolved: netfs: Fix kernel BUG in netfs_limit_iter() for ITER_KVEC iterators When a process crashes and the kernel writes a core dump to a 9P filesystem, __kernel_write() creates an ITER_KVEC iterator. This iterator reaches netfs_limit_iter() via netfs_unbuffered_write(), which only handles ITER_FOLIOQ, ITER_BVEC and ITER_XARRAY iterator types, hitting the BUG() for any other type. Fix this by adding netfs_limit_kvec() following the same pattern as netfs_limit_bvec(), since both kvec and bvec are simple segment arrays with pointer and length fields. Dispatch it from netfs_limit_iter() when the iterator type is ITER_KVEC.

References

https://git.kernel.org/stable/c/67e467a11f62ff64ad219dc6aa5459e132c79d14

https://git.kernel.org/stable/c/4bc2d72c7695cedf6d4e1a558924903c2b28a78e

https://git.kernel.org/stable/c/18c2e20b42dd21db599e42d05ddaeeb647b2bb6d

https://git.kernel.org/stable/c/00d6df7115f6972370974212de9088087820802e

Details

Source: Mitre, NVD

Published: 2026-04-22

Updated: 2026-04-23

Risk Information

CVSS v2

Base Score: 4.9

Vector: CVSS2#AV:L/AC:L/Au:N/C:N/I:N/A:C

Severity: Medium

CVSS v3

Base Score: 5.5

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Severity: Medium

EPSS

EPSS: 0.00018