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.
Affected products
gnu: gnutls; redhat: hardened images; redhat: openshift container platform; redhat: enterprise linux; redhat: enterprise linux for els; redhat: enterprise linux for ibm z systems; redhat: enterprise linux for ibm z systems els; redhat: enterprise linux for power little endian; redhat: enterprise linux for power little endian els; redhat: enterprise linux for eus; redhat: enterprise linux for ibm z systems eus; redhat: enterprise linux for power little endian eus; redhat: enterprise linux for update services for sap solutions; redhat: enterprise linux server for power little endian update services for sap solutions
References10
- access.redhat.com/errata/RHSA-2026:13274 Third Party Advisory
- access.redhat.com/errata/RHSA-2026:20611 Third Party Advisory
- access.redhat.com/errata/RHSA-2026:20612 Third Party Advisory
- access.redhat.com/errata/RHSA-2026:20613 Third Party Advisory
- access.redhat.com/errata/RHSA-2026:26319
- access.redhat.com/errata/RHSA-2026:26409
- access.redhat.com/errata/RHSA-2026:29197
- access.redhat.com/errata/RHSA-2026:29794
- access.redhat.com/errata/RHSA-2026:30004
- access.redhat.com/errata/RHSA-2026:30849
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 72 · as of 14 November 2026
- CWE
- CWE-475
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.