CVE-2026-42009
Gnutls: gnutls: denial of service via dtls packet reordering vulnerability
- State
- Published
- Severity
- 7.5 High
- Published
- May 18, 2026
- Updated
- Oct 30, 2026
- Reserved
- Apr 23, 2026
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 7.5 High | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | redhat |
| 3.1 | 7.5 High | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | redhat-SADP |
Weaknesses
- CWE-475 Undefined Behavior for Input to API
Affected Products
| Product | Versions |
|---|---|
gnutls |
|
Red Hat Enterprise Linux 10Red Hat |
|
Red Hat Enterprise Linux 10.0 Extended Update SupportRed Hat |
|
Red Hat Enterprise Linux 7 Extended Lifecycle SupportRed Hat |
|
Red Hat Enterprise Linux 8Red Hat |
|
Red Hat Enterprise Linux 8Red Hat |
|
Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update SupportRed Hat |
|
Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update SupportRed Hat |
|
Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-OnRed Hat |
|
Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-OnRed Hat |
|
Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update SupportRed Hat |
|
Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update SupportRed Hat |
|
Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-OnRed Hat |
|
Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-OnRed Hat |
|
Red Hat Enterprise Linux 8.8 Telecommunications Update ServiceRed Hat |
|
Red Hat Enterprise Linux 8.8 Telecommunications Update ServiceRed Hat |
|
Red Hat Enterprise Linux 8.8 Update Services for SAP SolutionsRed Hat |
|
Red Hat Enterprise Linux 8.8 Update Services for SAP SolutionsRed Hat |
|
Red Hat Enterprise Linux 9Red Hat |
|
Red Hat Enterprise Linux 9Red Hat |
|
Red Hat Enterprise Linux 9.2 Update Services for SAP SolutionsRed Hat |
|
Red Hat Enterprise Linux 9.4 Update Services for SAP SolutionsRed Hat |
|
Red Hat Enterprise Linux 9.6 Extended Update SupportRed Hat |
|
Red Hat OpenShift Container Platform 4.12Red Hat |
|
Red Hat OpenShift Container Platform 4.13Red Hat |
|
Red Hat OpenShift Container Platform 4.14Red Hat |
|
Red Hat OpenShift Container Platform 4.15Red Hat |
|
Red Hat OpenShift Container Platform 4.16Red Hat |
|
Red Hat OpenShift Container Platform 4.17Red Hat |
|
Red Hat OpenShift Container Platform 4.18Red Hat |
|
Red Hat OpenShift Container Platform 4.19Red Hat |
|
Red Hat OpenShift Container Platform 4.20Red Hat |
|
Red Hat OpenShift Container Platform 4.21Red Hat |
|
Red Hat OpenShift Container Platform 4.22Red Hat |
|
Cert Manager support for Red Hat OpenShift release 1.17Red Hat |
|
Cert Manager support for Red Hat OpenShift release 1.17Red Hat |
|
Cert Manager support for Red Hat OpenShift release 1.17Red Hat |
|
Cert Manager support for Red Hat OpenShift release 1.17Red Hat |
|
Cert Manager support for Red Hat OpenShift release 1.18Red Hat |
|
Cert Manager support for Red Hat OpenShift release 1.18Red Hat |
|
Cert Manager support for Red Hat OpenShift release 1.18Red Hat |
|
Cert Manager support for Red Hat OpenShift release 1.18Red Hat |
|
Cert Manager support for Red Hat OpenShift release 1.18Red Hat |
|
Cert Manager support for Red Hat OpenShift release 1.20Red Hat |
|
Red Hat AI Inference Server 3.2Red Hat |
|
Red Hat AI Inference Server 3.2Red Hat |
|
Red Hat AI Inference Server 3.2Red Hat |
|
Red Hat Discovery 2Red Hat |
|
Red Hat Discovery 2Red Hat |
|
Red Hat Hardened ImagesRed Hat |
|
Red Hat OpenShift AI 3.4Red Hat |
|
Red Hat Update Infrastructure 5Red Hat |
|
Red Hat Update Infrastructure 5Red Hat |
|
Red Hat Update Infrastructure 5Red Hat |
|
Red Hat Update Infrastructure 5Red Hat |
|
Red Hat Update Infrastructure 5Red Hat |
|
Red Hat Update Infrastructure 5Red Hat |
|
Red Hat Update Infrastructure 5Red Hat |
|
Red Hat Enterprise Linux 6Red Hat | |
Red Hat OpenShift Container Platform 4Red Hat | |
Red Hat OpenShift Container Platform 5Red Hat |
References
- RHSA-2026:13274vendor-advisory
- RHSA-2026:20611vendor-advisory
- RHSA-2026:20612vendor-advisory
- RHSA-2026:20613vendor-advisory
- RHSA-2026:26319vendor-advisory
- RHSA-2026:26409vendor-advisory
- RHSA-2026:29197vendor-advisory
- RHSA-2026:29794vendor-advisory
- RHSA-2026:30004vendor-advisory
- RHSA-2026:30849vendor-advisory
- RHSA-2026:30850vendor-advisory
- RHSA-2026:32962vendor-advisory
- RHSA-2026:33125vendor-advisory
- RHSA-2026:34372vendor-advisory
- RHSA-2026:34764vendor-advisory
- RHSA-2026:34788vendor-advisory
- RHSA-2026:36004vendor-advisory
- RHSA-2026:36005vendor-advisory
- RHSA-2026:36006vendor-advisory
- RHSA-2026:40762vendor-advisory
- RHSA-2026:41921vendor-advisory
- RHSA-2026:56786vendor-advisory
- RHSA-2026:56853vendor-advisory
- RHSA-2026:56911vendor-advisory
- RHSA-2026:57483vendor-advisory
- RHSA-2026:58981vendor-advisory
- RHSA-2026:59831vendor-advisory
- RHSA-2026:60019vendor-advisory
- RHSA-2026:65839vendor-advisory
- RHSA-2026:72502vendor-advisory
- RHSA-2026:74674vendor-advisory
- RHSA-2026:82304vendor-advisory
- RHSA-2026:82322vendor-advisory
- RHSA-2026:82347vendor-advisory
- RHSA-2026:82354vendor-advisory
- RHSA-2026:82372vendor-advisory
- RHSA-2026:82857vendor-advisory
- RHSA-2026:82888vendor-advisory
- https://access.redhat.com/security/cve/CVE-2026-42009vdb-entry
- RHBZ#2467279issue-tracking
- https://www.gnutls.org/security-new.html#GNUTLS-SA-2026-04-29-2
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42009.json
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