CVE-2025-40253

Description

Double-free corruption occurs in the s390 CTC MPC driver when mpc_rcvd_sweep_req() frees the mpcginfo structure, followed by ctcmpc_unpack_skb() freeing the same pointer. Clang's static analyzer flagged this ownership confusion. The duplicate kfree() corrupts slab metadata, potentially crashing the kernel or enabling exploitation.

Statement

Exclusively impacts s390 mainframes using Channel-to-Channel MPC networking. The CTC subsystem sees limited deployment outside legacy IBM environments.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score5.5N/A8.8
Attack VectorLocalN/AAdjacent Network
Attack ComplexityLowN/ALow
Privileges RequiredLowN/ANone
User InteractionNoneN/ANone
ScopeUnchangedN/AUnchanged
ConfidentialityNoneN/AHigh
Integrity ImpactNoneN/AHigh
Availability ImpactHighN/AHigh

Vector

Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

cve.org: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Understanding the Weakness (CWE)

Availability,Integrity

Technical Impact: DoS: Crash, Exit, or Restart

Frequently Asked Questions

Want to get errata notifications? Sign up here.