Network Performance Vulnerability in Linux Kernel by Linux Foundation

CVE-2025-21806

Summary

A vulnerability in the Linux kernel's network stack arises when the NAPI (New API) weight is set to zero, leading to erroneous behavior during packet handling. Specifically, the process_backlog function may incorrectly indicate that it has managed packets, resulting in the potential for infinite loops, resource exhaustion, and system instability. This issue necessitates root-level access to exploit, allowing an attacker to interfere with packet processing and potentially degrade system performance. A fix has been implemented to ensure that the NAPI weight remains non-zero, resolving the observed problems.

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