CVE Catalog

CVE-2025-40063

HighCVSS 7.0
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.12%

2th percentile - higher than 2% of all known CVEs

Summary

In the Linux kernel crypto compression subsystem, there is a mismatch in the order of alloc_ctx and free_ctx operations in scomp_alg and crypto_acomp_streams structures. Structure layout randomization can cause the function pointer order to be inconsistent, leading to errors.

Risk Assessment

This can lead to incorrect cryptographic compression/decompression behavior, potentially causing crashes or security vulnerabilities.

Recommendation

Apply the Linux kernel patch that removes the union from scomp_alg to ensure consistent structure layout.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS