CVE-2026-42009

HIGH

Gnutls: gnutls: denial of service via dtls packet reordering vulnerability

Title source: cna
STIX 2.1

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.

References (3)

Core 3
Core References
Vdb Entry, X_Refsource_Redhat vdb-entry x_refsource_redhat
https://access.redhat.com/security/cve/CVE-2026-42009
Issue Tracking, X_Refsource_Redhat issue-tracking x_refsource_redhat
RHBZ#2467279
https://bugzilla.redhat.com/show_bug.cgi?id=2467279
Vendor Advisory vendor-advisory x_refsource_redhat
RHSA-2026:13274
https://access.redhat.com/errata/RHSA-2026:13274

Scores

CVSS v3 7.5
EPSS 0.0022
EPSS Percentile 45.0%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-475
Status published
Products (8)
Red Hat/Red Hat Enterprise Linux 10
Red Hat/Red Hat Enterprise Linux 6
Red Hat/Red Hat Enterprise Linux 7
Red Hat/Red Hat Enterprise Linux 8
Red Hat/Red Hat Enterprise Linux 9
Red Hat/Red Hat Hardened Images
Red Hat/Red Hat Hardened Images 3.8.13-1.hum1
Red Hat/Red Hat OpenShift Container Platform 4
Published May 18, 2026
Tracked Since May 18, 2026