CVE-2026-53218

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description An issue exists in the netfilter module where the nft exthdr init() function passes a user-controlled priv->len variable to nft parse register store(), which marks a specific number of bytes in the register bitmap as initialized. When the NFT EXTHDR F PRESENT flag is set, the evaluation paths only write 1 byte via nft reg store8() or 4 bytes during TCP/DCCP error paths. If len is greater than 4, registers beyond the first are not written, causing them to retain uninitialized stack data from nft regs.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.