CVE-2026-31438

Severity CVSS v4.0:

Pending analysis

Type:

CWE-476 NULL Pointer Dereference

Publication date:

22/04/2026

Last modified:

19/05/2026

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.

Impact

Vector 3.x

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS v3.1 Severity and Metrics:

Base Score: 5.50 MEDIUM
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): None
Integrity (I): None
Availability (A): High

Base Score 3.x

5.50

Severity 3.x

MEDIUM

Vulnerable products and versions

CPE	From	Up to
cpe:2.3:o:linux:linux_kernel::::::::	6.8 (including)	6.12.80 (excluding)
cpe:2.3:o:linux:linux_kernel::::::::	6.13 (including)	6.18.21 (excluding)
cpe:2.3:o:linux:linux_kernel::::::::	6.19 (including)	6.19.11 (excluding)
cpe:2.3:o:linux:linux_kernel:7.0:rc1::::::
cpe:2.3:o:linux:linux_kernel:7.0:rc2::::::
cpe:2.3:o:linux:linux_kernel:7.0:rc3::::::
cpe:2.3:o:linux:linux_kernel:7.0:rc4::::::
cpe:2.3:o:linux:linux_kernel:7.0:rc5::::::
cpe:2.3:o:linux:linux_kernel:7.0:rc6::::::

To consult the complete list of CPE names with products and versions, see this page

CVE-2026-31438

Description

Impact

Vulnerable products and versions

References to Advisories, Solutions, and Tools