CVE-2026-43336
Information Leak in Linux Kernel ChaCha Implementation
Publication date: 2026-05-08
Last updated on: 2026-05-08
Assigner: kernel.org
Description
Description
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | * |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability exists in the Linux kernel's cryptographic library, specifically in the ChaCha implementation. The issue is that the local variable 'permuted_state' was not zeroized (cleared) before it went out of scope. Since the ChaCha permutation is invertible, an attacker could potentially use the 'permuted_state' to compute the original 'state' and thus recover the cryptographic key even after the permutation operation is complete.
The fix involved explicitly zeroizing the 'permuted_state' variable before it leaves scope to prevent sensitive key material from remaining in memory.
How can this vulnerability impact me? :
If exploited, this vulnerability could allow an attacker to recover cryptographic keys from memory by analyzing the 'permuted_state' variable that was not properly cleared. This could compromise the confidentiality and integrity of encrypted data protected by the ChaCha cipher within the Linux kernel.
Such a compromise could lead to unauthorized data access, decryption of sensitive information, or other security breaches depending on how the keys are used.
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, update your Linux kernel to a version where the issue has been resolved. The fix involves zeroizing the 'permuted_state' variable before it leaves scope to prevent key recovery.
Since this is a kernel-level vulnerability related to cryptographic state handling, applying the latest security patches or kernel updates from your Linux distribution is the recommended immediate step.