CVE-2026-43336

Summary

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 Software

VendorProductVersion RangeStatus
LinuxLinuxc08d0e647305c3f8f640010a56c9e4bafb9488d3 < e90ee961af515a484f091678ce58a4c3f7b73b02affected
LinuxLinuxc08d0e647305c3f8f640010a56c9e4bafb9488d3 < b416a4245f04a450c67a13e6d96056c37c5b33feaffected
LinuxLinuxc08d0e647305c3f8f640010a56c9e4bafb9488d3 < bd62d9b44464a6c20a34a74068e7a784d0afa04aaffected
LinuxLinuxc08d0e647305c3f8f640010a56c9e4bafb9488d3 < 066c760acead1fb743bae294dbd89f479ae43b9baffected
LinuxLinuxc08d0e647305c3f8f640010a56c9e4bafb9488d3 < 1d761e5a7340c46479fb2399598f331e4fe2c633affected
LinuxLinuxc08d0e647305c3f8f640010a56c9e4bafb9488d3 < 1933249263c3a98df79992f61a566476e4163bccaffected
LinuxLinuxc08d0e647305c3f8f640010a56c9e4bafb9488d3 < 91999af43ca2125e3b2c18fcfc02912ada02efc3affected
LinuxLinuxc08d0e647305c3f8f640010a56c9e4bafb9488d3 < e5046823f8fa3677341b541a25af2fcb99a5b1e0affected
LinuxLinux4.2affected
LinuxLinux0 < 4.2unaffected
LinuxLinux5.10.253 <= 5.10.*unaffected
LinuxLinux5.15.203 <= 5.15.*unaffected
LinuxLinux6.1.169 <= 6.1.*unaffected
LinuxLinux6.6.135 <= 6.6.*unaffected
LinuxLinux6.12.82 <= 6.12.*unaffected
LinuxLinux6.18.22 <= 6.18.*unaffected
LinuxLinux6.19.12 <= 6.19.*unaffected
LinuxLinux7.0 <= *unaffected

Weaknesses

References