Description
In the Linux kernel, the following vulnerability has been resolved: lib/crypto: chacha: Zeroize permuted_state before it leaves scope Since the ChaCha permutation is invertible, the local variable 'permuted_state' is sufficient to compute the original 'state', and thus the key, even after the permutation has been done. While the kernel is quite inconsistent about zeroizing secrets on the stack (and some prominent userspace crypto libraries don't bother at all since it's not guaranteed to work anyway), the kernel does try to do it as a best practice, especially in cases involving the RNG. Thus, explicitly zeroize 'permuted_state' before it goes out of scope.
Affected products
linux: linux kernel
References8
- git.kernel.org/stable/c/066c760acead1fb743bae294dbd89f479ae43b9b Patch
- git.kernel.org/stable/c/1933249263c3a98df79992f61a566476e4163bcc Patch
- git.kernel.org/stable/c/1d761e5a7340c46479fb2399598f331e4fe2c633 Patch
- git.kernel.org/stable/c/91999af43ca2125e3b2c18fcfc02912ada02efc3 Patch
- git.kernel.org/stable/c/b416a4245f04a450c67a13e6d96056c37c5b33fe Patch
- git.kernel.org/stable/c/bd62d9b44464a6c20a34a74068e7a784d0afa04a Patch
- git.kernel.org/stable/c/e5046823f8fa3677341b541a25af2fcb99a5b1e0 Patch
- git.kernel.org/stable/c/e90ee961af515a484f091678ce58a4c3f7b73b02 Patch
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 0% percentile: 37 · as of 13 November 2026
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