PT-2026-34938 · Linux · Linux Kernel

Published 2026-04-24 · Updated 2026-05-06 · CVE-2026-31586

Positive Technologies (AI Summary)

CVSS v3.1

7.8

High

Base vector

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

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description A use-after-free issue exists in the function cgwb release workfn(). The function calls css put(wb->blkcg css) and subsequently accesses wb->blkcg css again via blkcg unpin online(). If css put() drops the last reference, the blkcg can be freed asynchronously before blkcg unpin online() dereferences the pointer to access blkcg->online pin.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Use After Free

Weakness Enumeration

CWE-416

Related Identifiers

CVE-2026-31586

ECHO-E4CE-6885-778C

OPENSUSE-SU-2026:10703-1

Affected Products

Linux Kernel

References · 78

• https://security-tracker.debian.org/tracker/CVE-2026-31586 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-31586 · Vendor Advisory
• https://git.kernel.org/stable/c/115a5266749dcde7fe4127e8623d19c752088f69 · Patch
• https://osv.dev/vulnerability/BELL-CVE-2026-31586 · Vendor Advisory
• https://git.kernel.org/stable/c/8f5857be99f1ed1fa80991c72449541f634626ee · Patch
• https://ubuntu.com/security/CVE-2026-31586 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-31586 · Security Note
• https://git.kernel.org/stable/c/ea3af09eb87d8f8708c66747fcf1a2762902e839 · Patch
• https://git.kernel.org/stable/c/67cb119d32f35e32acd0393bbeb318b2bb1fdafe · Patch
• https://git.kernel.org/stable/c/dfc8292a1d6782c76b626315605e0585a5a18447 · Patch
• https://osv.dev/vulnerability/openSUSE-SU-2026:10703-1 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-31586 · Security Note
• https://git.kernel.org/stable/c/50879a3c1faf06e661090015d59e2127255cff27 · Patch
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-31586 · Vendor Advisory
• https://docs.bell-sw.com/security/cves/CVE-2026-31586 · Note