CVE-2026-42009
7.5 · HIGHOverview
CVE-2026-42009 is a high-severity vulnerability affecting gnu gnutls. It was published on May 18, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from gnu. Update gnutls to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
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References
Frequently Asked Questions
What is CVE-2026-42009?
CVE-2026-42009 is a high-severity vulnerability affecting gnu gnutls. It was published on May 18, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
How severe is CVE-2026-42009?
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-42009?
Check the references section for vendor advisories and patches from gnu. Update gnutls to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-42009?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-42009 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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