TOCTOU Vulnerability in Linux Kernel Affecting Memory-Mapped Buffers

CVE-2026-53250

What is CVE-2026-53250?

A vulnerability has been identified in the Linux kernel that allows attackers to exploit race conditions when accessing the TX metadata area in memory-mapped buffers. This issue stems from the way variables are referenced in the xsk_skb_metadata() function, permitting a malicious userspace application to overwrite these values between necessary reads. Consequently, this results in bypassing critical bounds checks and may lead to out-of-bounds memory access during checksum computations within the transmit pathway. A solution has been implemented to mitigate this risk by ensuring local caching of these values, thereby maintaining data consistency and preventing security breaches.

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