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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-42009 Detail

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://access.redhat.com/errata/RHSA-2026:13274 Red Hat, Inc. Third Party Advisory 
https://access.redhat.com/errata/RHSA-2026:20611 Red Hat, Inc. Third Party Advisory 
https://access.redhat.com/errata/RHSA-2026:20612 Red Hat, Inc. Third Party Advisory 
https://access.redhat.com/errata/RHSA-2026:20613 Red Hat, Inc. Third Party Advisory 
https://access.redhat.com/security/cve/CVE-2026-42009 Red Hat, Inc. Third Party Advisory 
https://bugzilla.redhat.com/show_bug.cgi?id=2467279 Red Hat, Inc. Issue Tracking  Third Party Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-475 Undefined Behavior for Input to API Red Hat, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

6 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-42009
NVD Published Date:
05/18/2026
NVD Last Modified:
06/08/2026
Source:
Red Hat, Inc.