CVE-2025-39802
published 2025-09-15CVE-2025-39802: In the Linux kernel, the following vulnerability has been resolved: lib/crypto: arm/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: 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.
Affected
6 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.16.5-1 (forky) | linux 6.16.5-1 (forky) |
| linux | linux | — | — |
| linux | linux | >= 773426f4771bdd82ac5c834bf4c1775315c73a46 < 87bdfba903be7084cb3ee04032b14a81181fe413 | 87bdfba903be7084cb3ee04032b14a81181fe413 |
| linux | linux | >= 773426f4771bdd82ac5c834bf4c1775315c73a46 < 52c3e242f4d0043186b70d65460ba1767f27494a | 52c3e242f4d0043186b70d65460ba1767f27494a |
| linux | linux_kernel | >= 0 < 6.16.5-1 | 6.16.5-1 |
| linux | linux_kernel | >= 6.16 < 6.16.4 | 6.16.4 |
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
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OSV
CVE-2025-39802: In the Linux kernel, the following vulnerability has been resolved: lib/crypto: arm/poly1305: Fix register corruption in no-SIMD contexts Restore the
osv·2025-09-15·CVSS 7.8
CVE-2025-39802 [HIGH] CVE-2025-39802: In the Linux kernel, the following vulnerability has been resolved: lib/crypto: arm/poly1305: Fix register corruption in no-SIMD contexts Restore the
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.
GHSA
GHSA-xjw6-gqc2-j75x: In the Linux kernel, the following vulnerability has been resolved:
lib/crypto: arm/poly1305: Fix register corruption in no-SIMD contexts
Restore th
ghsa_unreviewed·2025-09-15
CVE-2025-39802 [HIGH] GHSA-xjw6-gqc2-j75x: In the Linux kernel, the following vulnerability has been resolved:
lib/crypto: arm/poly1305: Fix register corruption in no-SIMD contexts
Restore th
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.
Red Hat
kernel: lib/crypto: arm/poly1305: Fix register corruption in no-SIMD contexts
vendor_redhat·2025-09-15·CVSS 7.8
CVE-2025-39802 [HIGH] kernel: lib/crypto: arm/poly1305: Fix register corruption in no-SIMD contexts
kernel: lib/crypto: arm/poly1305: Fix register corruption in no-SIMD contexts
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_sim
Debian
CVE-2025-39802: linux - In the Linux kernel, the following vulnerability has been resolved: lib/crypto:...
vendor_debian·2025·CVSS 7.8
CVE-2025-39802 [HIGH] CVE-2025-39802: linux - In the Linux kernel, the following vulnerability has been resolved: lib/crypto:...
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.
Scope: local
bookworm: resolved
bullseye: resolved
forky:
No detection rules found.
No public exploits indexed.
2025-09-15
Published