CVE-2026-42009

Publication date 30 April 2026

Last updated 22 May 2026

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

7.5 · High

Score breakdown

Description

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.

Status

Package Ubuntu Release Status
gnutls28 26.04 LTS resolute
Fixed 3.8.12-2ubuntu1.1
25.10 questing
Fixed 3.8.9-3ubuntu2.2
24.04 LTS noble
Fixed 3.8.3-1.1ubuntu3.6
22.04 LTS jammy
Fixed 3.7.3-4ubuntu1.9
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
gnutls28

Severity score breakdown

CVSS version: CVSS v3.0

Base score 7.5 · High

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

Other references

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