CVE-2026-42009
Gnutls: gnutls: denial of service via dtls packet reordering vulnerability
CVSS Score
7.5
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-475 |
| Vendor | red hat |
| Product | red hat enterprise linux 10 |
| Published | May 18, 2026 |
| Last Updated | May 18, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
Red Hat / Red Hat Enterprise Linux 10
All versions affected Red Hat / Red Hat Enterprise Linux 6
All versions affected Red Hat / Red Hat Enterprise Linux 7
All versions affected Red Hat / Red Hat Enterprise Linux 8
All versions affected Red Hat / Red Hat Enterprise Linux 9
All versions affected Red Hat / Red Hat Hardened Images
All versions affected Red Hat / Red Hat OpenShift Container Platform 4
All versions affected References
Credits
Red Hat would like to thank Joshua Rogers (AISLE Research Team) for reporting this issue.