Status: UPDATED | Advisory ID: CVE-2026-42009
| CVE | CVE-2026-42009 |
| CVSS Score / Version | 7.5 (High) / CVSS v3.1 |
| Updated | 2026-10-02 |
| CVSS Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| CVSS Prose | attack vector is network; attack complexity is low; privileges required is none; user interaction is none; scope is unchanged; confidentiality impact is none; integrity impact is none; availability impact is high. |
| Affected products | see table below |
| Classified as | CWE-475 (Undefined Behavior for Input to API) |
| Vendor | Product | Affected Versions | Patch Status |
|---|---|---|---|
| Red Hat | Enterprise Linux | ||
| Red Hat | OpenShift Container Platform | ||
| Red Hat | hardened_images | ||
| Red Hat | Red Hat OpenShift AI 3.4 | ||
| Red Hat | Red Hat Enterprise Linux 10 | ||
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | ||
| Red Hat | Red Hat Enterprise Linux 8 | ||
| Red Hat | Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | ||
| Red Hat | Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On | ||
| Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | ||
| Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On | ||
| Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | ||
| Red Hat | Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions | ||
| Red Hat | Red Hat Enterprise Linux 9 | ||
| Red Hat | Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions | ||
| Red Hat | Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions | ||
| Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | ||
| Red Hat | Red Hat Update Infrastructure 5 | ||
| Red Hat | Red Hat Hardened Images | ||
| Red Hat | Red Hat OpenShift Container Platform 4.12 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.13 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.14 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.15 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.16 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.17 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.18 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.19 | ||
| Red Hat | Red Hat OpenShift Container Platform 4 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.20 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.21 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.22 | ||
| Red Hat | Red Hat Enterprise Linux 7 Extended Lifecycle Support | ||
| gnu | gnutls | ||
| Red Hat | Cert Manager support for Red Hat OpenShift release 1.20 | ||
| Red Hat | Red Hat AI Inference Server 3.2 | ||
| Red Hat | Red Hat Discovery 2 | ||
| Red Hat | enterprise_linux_for_els | ||
| Red Hat | enterprise_linux_for_ibm_z_systems | ||
| Red Hat | enterprise_linux_for_ibm_z_systems_els | ||
| Red Hat | enterprise_linux_for_power_little_endian | ||
| Red Hat | enterprise_linux_for_power_little_endian_els | ||
| Red Hat | enterprise_linux_for_eus | ||
| Red Hat | enterprise_linux_for_ibm_z_systems_eus | ||
| Red Hat | enterprise_linux_for_power_little_endian_eus | ||
| Red Hat | enterprise_linux_for_update_services_for_sap_solutions | ||
| Red Hat | enterprise_linux_server_for_power_little_endian_update_services_for_sap_solutions |
| Subsystems | Core Infrastructure, EWS Workstation Delivery/Virtualization |
| Sectors | All Sectors |
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. (NVD)
Monitor Red Hat's and gnu's web pages for any future patch releases.
| Source | Reference |
|---|---|
| NVD | https://nvd.nist.gov/vuln/detail/CVE-2026-42009 |
| CVE | https://www.cve.org/CVERecord?id=CVE-2026-42009 |