SB2026050905 - Information Exposure Through Timing Discrepancy in Linux kernel ipv4
Published: May 9, 2026
Security Bulletin ID
SB2026050905
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Data manipulation
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Information Exposure Through Timing Discrepancy (CVE-ID: CVE-2026-43384)
CWE-ID: CWE-208 - Information Exposure Through Timing Discrepancy
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to bypass message authentication.
The vulnerability exists due to observable timing differences in MAC comparison in tcp-ao when verifying authentication codes. A remote attacker can measure response timing during crafted network interactions to bypass message authentication.
Remediation
Install update from vendor's website.