CVE-2026-5419: gnutls28 Observable Timing Discrepancy

Vulnerability summary

CVE-2026-5419 is a low (CVSS 3.7) Observable Timing Discrepancy vulnerability in gnutls28. EPSS estimates a 0.63% chance of exploitation in the next 30 days, higher than 49.2% of scored vulnerabilities.

Timeline

1. 01-06-2026
   PublishedVulnerability first disclosed.
2. 14-10-2026
   Last modifiedVulnerability information updated.

Description

A flaw was found in gnutls. The PKCS#7 padding check, performed during decryption, was not constant-time. This timing side-channel could allow a remote attacker to potentially leak sensitive information about the padding bytes through observable timing differences. This vulnerability is a form of information disclosure.

• CWE-208Observable Timing DiscrepancyTwo separate operations in a product require different amounts of time to complete, in a way that is observable to an actor and reveals security-relevant information about the state of the product, such as whether a particular operation was successful or not.