CVE-2026-43336: lib/crypto: chacha: Zeroize permuted_state before it leaves scope
In the Linux kernel, the following vulnerability has been resolved:
lib/crypto: chacha: Zeroize permutedstate before it leaves scope
Since the ChaCha permutation is invertible, the local variable 'permutedstate' 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 'permutedstate' before it goes out of scope.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-43336?
CVE-2026-43336 has a moderate severity rating due to potential information leakage.
How do I fix CVE-2026-43336?
To resolve CVE-2026-43336, update your Linux kernel to the latest version where this vulnerability has been patched.
What systems are affected by CVE-2026-43336?
CVE-2026-43336 affects certain versions of the Linux kernel that utilize the ChaCha encryption algorithm.
What is the main issue with CVE-2026-43336?
The main issue with CVE-2026-43336 is that it does not properly zeroize the 'permuted_state' variable, leading to potential data exposure.
When was CVE-2026-43336 disclosed?
CVE-2026-43336 was disclosed as part of security updates for the Linux kernel.