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Vulnerability DatabaseCVE-2025-21868
CVE-2025-21868:
Linux Kernel vulnerability analysis and mitigation
Overview
CVE-2025-21868 was disclosed on March 27, 2025, affecting the Linux kernel. The vulnerability relates to a buffer cache usage issue with large MAXSKBFRAGS values, specifically in the network subsystem (NVD).
Technical details
The vulnerability manifests when the kernel is built with MAXSKBFRAGS=45, where SKBWITHOVERHEAD(1024) is smaller than GROMAXHEAD. This condition affects the napigetfrags() function, which uses the page frag allocator and triggers a warning in the netifnapiaddweightlocked function (NVD).
Impact
The vulnerability affects the network subsystem's buffer management functionality, potentially leading to system instability or crashes when processing network packets under specific conditions (NVD).
Mitigation and workarounds
The issue has been resolved in the Linux kernel through updates to ensure that small head cache will fit both TCP and GRO allocation, with modifications to napiallocskb() and _netdevalloc_skb() functions to properly handle kmalloc() usage (NVD).
Additional resources
Source: This report was generated using AI
Related Linux Kernel vulnerabilities:
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