PT-2026-20451 · Linux · Linux Kernel

Shinichiro · Published 2026-01-01 · Updated 2026-03-18 · CVE-2026-23225

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 The Linux kernel contains a flaw in the MMCID management code related to handling CPU ID (CID) transitions. Specifically, the issue arises when a task exits while in a transitional state, leading to an out-of-bounds access during CID removal. The sched mm cid exit() function incorrectly assumes the CID is CPU-owned, potentially causing issues when the TRANSIT flag is set. This can occur when a task switches between per-CPU and per-task CID modes without proper synchronization, resulting in a use-after-free condition. The vulnerability was identified through KASAN (Kernel Address Sanitizer) and reported by Shinichiro.

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

Exploit

Related Identifiers

CVE-2026-23225

ECHO-C39F-A049-8C5E

OPENSUSE-SU-2026:10387-1

Affected Products

Linux Kernel

References · 46

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23225.json · Exploit
• https://nvd.nist.gov/vuln/detail/CVE-2026-23225 · Security Note
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-23225 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2026-23225 · Vendor Advisory
• https://osv.dev/vulnerability/ROOT-OS-DEBIAN-11-CVE-2026-23225 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-23225 · Vendor Advisory
• https://osv.dev/vulnerability/openSUSE-SU-2026:10387-1 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-23225 · Security Note
• https://osv.dev/vulnerability/CVE-2026-23225 · Vendor Advisory
• https://osv.dev/vulnerability/ROOT-OS-DEBIAN-12-CVE-2026-23225 · Vendor Advisory
• https://osv.dev/vulnerability/ROOT-OS-DEBIAN-13-CVE-2026-23225 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-23225 · Vendor Advisory
• https://suse.com/security/cve/CVE-2026-23234 · Note
• https://suse.com/security/cve/CVE-2025-71237 · Note
• https://suse.com/security/cve/CVE-2025-71231 · Note