cbcvebase.
CVE-2025-40063
published 2025-10-28

CVE-2025-40063: In the Linux kernel, the following vulnerability has been resolved: crypto: comp - Use same definition of context alloc and free ops In commit 42d9f6c77479…

PriorityP430high7CVSS 3.1
AVLACHPRLUINSUCHIHAH
EPSS
0.12%
2.3th percentile
In the Linux kernel, the following vulnerability has been resolved: crypto: comp - Use same definition of context alloc and free ops In commit 42d9f6c77479 ("crypto: acomp - Move scomp stream allocation code into acomp"), the crypto_acomp_streams struct was made to rely on having the alloc_ctx and free_ctx operations defined in the same order as the scomp_alg struct. But in that same commit, the alloc_ctx and free_ctx members of scomp_alg may be randomized by structure layout randomization, since they are contained in a pure ops structure (containing only function pointers). If the pointers within scomp_alg are randomized, but those in crypto_acomp_streams are not, then the order may no longer match. This fixes the problem by removing the union from scomp_alg so that both crypto_acomp_streams and scomp_alg will share the same definition of alloc_ctx and free_ctx, ensuring they will always have the same layout.

Affected

9 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.17.6-1 (forky)linux 6.17.6-1 (forky)
linuxlinux
linuxlinux>= 42d9f6c774790d290c175e8775ce9f1366438098 < 779d3b6f2d32c5f1da6163e959abe1e1ffe2945b779d3b6f2d32c5f1da6163e959abe1e1ffe2945b
linuxlinux>= 42d9f6c774790d290c175e8775ce9f1366438098 < f75f66683ded09f7135aef2e763c245a07c8271af75f66683ded09f7135aef2e763c245a07c8271a
linuxlinux_kernel>= 0 < 6.17.6-16.17.6-1
linuxlinux_kernel>= 0 < 6.17.0-14.146.17.0-14.14
linuxlinux_kernel>= 6.16.0 < 6.17.36.17.3
ubuntulinux-aws
ubuntulinux-oracle

CVSS provenance

nvdv3.17.0HIGHCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
vendor_redhat6.1MEDIUM
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