CVE-2026-42009
A remote attacker could exploit an issue in the Datagram Transport Layer Security (DTLS) packet reordering logic.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.33%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 1.33% probability · 70th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-475
- Affected
- 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
- Source
- secalert@redhat.com
References
- https://access.redhat.com/errata/RHSA-2026:13274Third Party Advisory
- https://access.redhat.com/errata/RHSA-2026:20611Third Party Advisory
- https://access.redhat.com/errata/RHSA-2026:20612Third Party Advisory
- https://access.redhat.com/errata/RHSA-2026:20613Third Party Advisory
- https://access.redhat.com/errata/RHSA-2026:26319
- https://access.redhat.com/errata/RHSA-2026:26409
- https://access.redhat.com/errata/RHSA-2026:29197
- https://access.redhat.com/errata/RHSA-2026:29794
- https://access.redhat.com/errata/RHSA-2026:30004
- https://access.redhat.com/errata/RHSA-2026:30849
- https://access.redhat.com/errata/RHSA-2026:30850
- https://access.redhat.com/errata/RHSA-2026:32962
- https://access.redhat.com/errata/RHSA-2026:33125
- https://access.redhat.com/errata/RHSA-2026:34372
- https://access.redhat.com/errata/RHSA-2026:34764
- https://access.redhat.com/errata/RHSA-2026:34788
- https://access.redhat.com/errata/RHSA-2026:36004
- https://access.redhat.com/errata/RHSA-2026:36005
- https://access.redhat.com/errata/RHSA-2026:36006
- https://access.redhat.com/errata/RHSA-2026:40762
- https://access.redhat.com/errata/RHSA-2026:41921
- https://access.redhat.com/errata/RHSA-2026:56786
- https://access.redhat.com/errata/RHSA-2026:56853
- https://access.redhat.com/errata/RHSA-2026:56911
- https://access.redhat.com/errata/RHSA-2026:57483
- https://access.redhat.com/errata/RHSA-2026:58981
- https://access.redhat.com/errata/RHSA-2026:59831
- https://access.redhat.com/errata/RHSA-2026:60019
- https://access.redhat.com/security/cve/CVE-2026-42009Third Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2467279Issue Tracking, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.