Undefined Behavior for Input to API Affecting gnutls28 package, versions <3.6.13-2ubuntu1.12+esm2


Severity

Recommended
medium

Based on Ubuntu security rating.

Threat Intelligence

EPSS
1.34% (68th percentile)

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  • Snyk IDSNYK-UBUNTU2004-GNUTLS28-16355171
  • published7 Jul 2026
  • disclosed18 May 2026

Introduced: 18 May 2026

CVE-2026-42009  (opens in a new tab)
CWE-475  (opens in a new tab)

How to fix?

Upgrade Ubuntu:20.04 gnutls28 to version 3.6.13-2ubuntu1.12+esm2 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream gnutls28 package and not the gnutls28 package as distributed by Ubuntu. See How to fix? for Ubuntu:20.04 relevant fixed versions and status.

A flaw was found in gnutls. A remote attacker could exploit an issue in the Datagram Transport Layer Security (DTLS) packet reordering logic. The comparator function, responsible for ordering DTLS packets by sequence numbers, did not correctly handle packets with duplicate sequence numbers. This could lead to unstable packet ordering or undefined behavior, resulting in a denial of service.

CVSS Base Scores

version 3.1