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Vulnerability DatabaseCVE-2025-21995
CVE-2025-21995:
Linux Kernel vulnerability analysis and mitigation
Overview
A reference count leak vulnerability was discovered in the Linux kernel's DRM scheduler component (CVE-2025-21995). The vulnerability was disclosed on April 3, 2025, affecting the fence reference counting mechanism in the drm/sched subsystem (NVD).
Technical details
The vulnerability occurs when the last_scheduled fence leaks during entity termination due to a cleanup callback failure. Specifically, when an entity is being killed and the dma_fence_add_callback() operation fails, the reference count of the previous fence is not properly decremented, leading to a resource leak (NVD).
Impact
The reference count leak in the DRM scheduler could potentially lead to resource exhaustion in the Linux kernel, though the specific impact severity has not been fully assessed as the CVSS score was not yet assigned at the time of disclosure (NVD).
Mitigation and workarounds
The vulnerability has been fixed in various Linux distributions. Debian has marked this as fixed in multiple releases including bullseye (5.10.234-1), bookworm (6.1.133-1), trixie (6.12.21-1), and sid (6.12.22-1) (Debian Tracker).
Additional resources
Linux Distribution fix status
Fix availability across major Linux distributions and their releases.
Source: This report was generated using AI
Related Linux Kernel vulnerabilities:
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