Description
In the Linux kernel, the following vulnerability has been resolved: crypto: af-alg - fix NULL pointer dereference in scatterwalk The AF_ALG interface fails to unmark the end of a Scatter/Gather List (SGL) when chaining a new af_alg_tsgl structure. If a sendmsg() fills an SGL exactly to MAX_SGL_ENTS, the last entry is marked as the end. A subsequent sendmsg() allocates a new SGL and chains it, but fails to clear the end marker on the previous SGL's last data entry. This causes the crypto scatterwalk to hit a premature end, returning NULL on sg_next() and leading to a kernel panic during dereference. Fix this by explicitly unmarking the end of the previous SGL when performing sg_chain() in af_alg_alloc_tsgl().
Affected products
linux: linux kernel
References8
- git.kernel.org/stable/c/00cbdec17c15d024a1c5002c7365df7624a18a75 Patch
- git.kernel.org/stable/c/44eafa39363e8d5dfda6a8c6eb6b45458ed4b948 Patch
- git.kernel.org/stable/c/4b03ab0a587ec57eb7ddb5c115d84a42896f60f7 Patch
- git.kernel.org/stable/c/62397b493e14107ae82d8b80938f293d95425bcb Patch
- git.kernel.org/stable/c/7195350fb78538c25cd790d703f8f2c73ee0d395 Patch
- git.kernel.org/stable/c/7cdf2c6381b21ab5ccf8116750d5582fcd6c0f49 Patch
- git.kernel.org/stable/c/f48d3dd99199180cf37d6253550c55e86372309a Patch
- git.kernel.org/stable/c/f9acceae7b004956851fd4268edf9f518a9bce04 Patch
Metrics
- CVSS 3.1
-
5.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 2 · as of 13 November 2026
- CWE
- CWE-476
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