PT-2026-33746 · Linux · Linux Kernel

Published 2026-04-20 · Updated 2026-06-05 · CVE-2026-31429

Positive Technologies (AI Summary)

CVSS v3.1

5.5

Medium

Base vector

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

Name of the Vulnerable Software and Affected Versions Linux kernel versions 6.3 through 6.12.81

Description A slab cross-cache free issue exists in the Linux kernel when KFENCE is enabled. The skb kfree head() function uses skb end offset to distinguish between skb heads allocated from skb small head cache and generic kmalloc caches. Because kfence ksize() returns the exact requested allocation size rather than the slab bucket size, an object allocated via kzalloc() that matches the SKB SMALL HEAD CACHE SIZE can be misclassified. This leads to the object being incorrectly freed to the skb small head cache instead of the original kmalloc cache.

Recommendations Update the Linux kernel to version 6.12.82 or later.

Fix

Memory Leak

Weakness Enumeration

CWE-401

Related Identifiers

CVE-2026-31429

OESA-2026-2581

Affected Products

Linux Kernel

References · 119

• https://nvd.nist.gov/vuln/detail/CVE-2026-23312 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-31505 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-31570 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-31699 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-43273 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-31738 · Security Note
• https://git.kernel.org/stable/c/128b03ccb2582a643983a48a37fda58df80edbde · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2026-23243 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-31533 · Security Note
• https://cve.org/CVERecord?id=CVE-2026-31429 · Security Note
• https://git.kernel.org/stable/c/0f42e3f4fe2a58394e37241d02d9ca6ab7b7d516 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2025-71132 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-31532 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-31546 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-31398 · Security Note