cbcvebase.
CVE-2025-39804
published 2025-09-15

CVE-2025-39804: In the Linux kernel, the following vulnerability has been resolved: lib/crypto: arm64/poly1305: Fix register corruption in no-SIMD contexts Restore the SIMD…

PriorityP338high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.23%
13.9th percentile
In the Linux kernel, the following vulnerability has been resolved: lib/crypto: arm64/poly1305: Fix register corruption in no-SIMD contexts Restore the SIMD usability check that was removed by commit a59e5468a921 ("crypto: arm64/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.

Affected

9 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.16.5-1 (forky)linux 6.16.5-1 (forky)
linuxlinux
linuxlinux>= a59e5468a921937cb7317892779c67046ad9f5cc < ef74efa598b7bbc5c24509f7f56af2806f81c339ef74efa598b7bbc5c24509f7f56af2806f81c339
linuxlinux>= a59e5468a921937cb7317892779c67046ad9f5cc < eec76ea5a7213c48529a46eed1b343e5cee3aaabeec76ea5a7213c48529a46eed1b343e5cee3aaab
linuxlinux_kernel>= 0 < 6.16.5-16.16.5-1
linuxlinux_kernel>= 6.16 < 6.16.46.16.4
msrccbl2_tar_1.34-3_on_cbl_mariner_2.0
msrccbl_mariner_2.0_arm
msrccbl_mariner_2.0_x64

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8LOW
vendor_redhat7.8HIGH
vendor_msrc6.2MEDIUM
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