CVE-2026-42009

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

CVSS 3.1 7.5 HIGHCheck source for fixed versionsKEV status unknown

Original advisory

cve-program · CVE-2026-42009

Published

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.

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Affected versions, risk and source history

Exploitation and risk

Source status

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Risk history

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Advisory history

4 saved versions

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4 Nov 2026 23:54:02 UTC