CVE-2026-43384
Constant-Time MAC Comparison Fix in Linux Kernel TCP-AO
Publication date: 2026-05-08
Last updated on: 2026-05-08
Assigner: kernel.org
Description
Description
CVSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | * |
| linux_kernel | 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 in the Linux kernel relates to the way Message Authentication Codes (MACs) are compared in the net/tcp-ao component.
The issue was that MAC comparisons were not done in constant time, which could allow timing attacks.
The fix involved using an appropriate helper function to ensure MAC comparisons are performed in constant time, preventing attackers from gaining information based on the time it takes to compare MACs.
How can this vulnerability impact me? :
If exploited, this vulnerability could allow an attacker to perform timing attacks to potentially deduce the MAC values used in TCP authentication.
This could lead to unauthorized access or manipulation of network communications that rely on these MACs for integrity and authentication.