CVE-2025-39802lib/crypto: arm/poly1305: Fix register corruption in no-SIMD contexts
Updated under an hour ago ()
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No exploitation reported and no EPSS estimate yet.
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In the Linux kernel, the following vulnerability has been resolved: lib/crypto: arm/poly1305: Fix register corruption in no-SIMD contexts Restore the SIMD usability check that was removed by commit 773426f4771b ("crypto: arm/poly1305 - Add block-only interface"). This safety check is cheap and is well worth eliminating a footgun. While the Poly1305 functions should not be called when SIMD registers are unusable, if they are anyway, they should just do the right thing instead of corrupting random tasks' registers and/or computing incorrect MACs. Fixing this is also needed for poly1305_kunit to pass. Just use may_use_simd() instead of the original crypto_simd_usable(), since poly1305_kunit won't rely on crypto_simd_disabled_for_test.
- CVSS
- 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Weakness (CWE)
- Not given
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Linux
- NVD analysis
- Modified
- Record last updated
- Aug 5, 2026
- First seen by InfoSec Signals
- Oct 19, 2026
Affected products
Linux Linux linux:linux (from the name) | 773426f4771bdd82ac5c834bf4c1775315c73a46 builds before 87bdfba903be7084cb3ee04032b14a81181fe413; 773426f4771bdd82ac5c834bf4c1775315c73a46 builds before 52c3e242f4d0043186b70d65460ba1767f27494a | CNA record |
linux linux_kernel linux:linux_kernel | from 6.16 before 6.16.4 | NVD |
References
- https://git.kernel.org/stable/c/87bdfba903be7084cb3ee04032b14a81181fe413patch
- https://git.kernel.org/stable/c/52c3e242f4d0043186b70d65460ba1767f27494apatch
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.