CVE-2026-42009: Undefined Behavior for Input to API
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.
AI Analysis
Technical Summary
This advisory covers security fixes in Red Hat OpenShift Container Platform 4.21.23, specifically addressing vulnerabilities in the GnuTLS library and Linux kernel SMB client. The GnuTLS fixes include a denial of service vulnerability caused by DTLS packet reordering (CVE-2026-42009), an authentication bypass vulnerability via a NUL character in the username (CVE-2026-42010), and other related issues. Additionally, the Linux kernel SMB client was updated to reject userspace cifs.spnego descriptions (CVE-2026-46243). These vulnerabilities are part of a broader set of fixes included in the release. Red Hat provides updated container images and RPM packages to remediate these issues. Users are encouraged to upgrade using the OpenShift CLI or web console following Red Hat's documented procedures.
Potential Impact
The vulnerabilities addressed include denial of service conditions and authentication bypasses that could affect the security and stability of OpenShift Container Platform deployments. The denial of service via DTLS packet reordering could disrupt secure communications. The authentication bypass via a NUL character in the username could allow unauthorized access under certain conditions. The SMB client fix prevents potentially unsafe userspace descriptions. These issues collectively pose a high security risk if left unpatched.
Mitigation Recommendations
Red Hat has released updated container images and RPM packages that fix the described vulnerabilities. Users of OpenShift Container Platform 4.21 should upgrade to version 4.21.23 or later as soon as the updated packages and images are available in their release channel. Upgrades can be performed using the OpenShift CLI (oc) or the web console. Detailed upgrade instructions are available in Red Hat's official documentation. There are no indications that these issues are already mitigated or require no action. Patch status is confirmed by Red Hat advisories.
CVE-2026-42009: Undefined Behavior for Input to API
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 v3.1
Score 7.5high
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This advisory covers security fixes in Red Hat OpenShift Container Platform 4.21.23, specifically addressing vulnerabilities in the GnuTLS library and Linux kernel SMB client. The GnuTLS fixes include a denial of service vulnerability caused by DTLS packet reordering (CVE-2026-42009), an authentication bypass vulnerability via a NUL character in the username (CVE-2026-42010), and other related issues. Additionally, the Linux kernel SMB client was updated to reject userspace cifs.spnego descriptions (CVE-2026-46243). These vulnerabilities are part of a broader set of fixes included in the release. Red Hat provides updated container images and RPM packages to remediate these issues. Users are encouraged to upgrade using the OpenShift CLI or web console following Red Hat's documented procedures.
Potential Impact
The vulnerabilities addressed include denial of service conditions and authentication bypasses that could affect the security and stability of OpenShift Container Platform deployments. The denial of service via DTLS packet reordering could disrupt secure communications. The authentication bypass via a NUL character in the username could allow unauthorized access under certain conditions. The SMB client fix prevents potentially unsafe userspace descriptions. These issues collectively pose a high security risk if left unpatched.
Mitigation Recommendations
Red Hat has released updated container images and RPM packages that fix the described vulnerabilities. Users of OpenShift Container Platform 4.21 should upgrade to version 4.21.23 or later as soon as the updated packages and images are available in their release channel. Upgrades can be performed using the OpenShift CLI (oc) or the web console. Detailed upgrade instructions are available in Red Hat's official documentation. There are no indications that these issues are already mitigated or require no action. Patch status is confirmed by Red Hat advisories.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:29794
- Cve Count
- 2
- Additional Cves
- ["CVE-2026-46331"]
- State
- PUBLISHED
Threat ID: 6a4452ea27e9c797198e1b20
Added to database: 06/30/2026, 23:36:10 UTC
Last enriched: 08/06/2026, 23:55:32 UTC
Last updated: 09/10/2026, 19:42:39 UTC
Views: 241
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