Linux Kernel Vulnerability: MAC Comparison Timing Attack Mitigation

CVE-2025-40204

What is CVE-2025-40204?

A timing attack vulnerability was identified in the Linux kernel concerning the MAC (Message Authentication Code) comparison process. To mitigate the risk of such attacks, which exploit the timing discrepancies in operations for sensitive data, the kernel now implements a constant-time comparison using an appropriate helper function. This update is essential to reinforce the integrity of communications and protect against potential exploitation by adversaries.

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