CVE-2026-99256
Description
A flaw was found in the Linux kernel's Device Mapper cache (dm-cache) subsystem. Improper lock ownership handling in the background work locking mechanism allows a lock to be released by a different process than the one that acquired it when suspending and resuming a cache device. A local user with administrative privileges could trigger this condition, leading to kernel locking inconsistencies and a potential Denial of Service (DoS).
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 Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 4.4 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | High | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | None | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Integrity,Availability
Technical Impact: Modify Application Data; DoS: Instability; DoS: Crash, Exit, or Restart
When a resource is not properly locked, an attacker could modify the resource while it is being operated on by the product. This might violate the product's assumption that the resource will not change, potentially leading to unexpected behaviors.
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