Ubuntu Security Notices USN-8398-3 USN-8398-3: nginx vulnerability Publication date 15 June 2026 Overview nginx could be made to consume excessive resources if it received specially crafted network traffic. Releases 26.04 LTS 25.10 24.04 LTS 22.04 LTS Open side navigation Close side navigation Packages Details Update instructions References Related notices Packages nginx - small, powerful, scalable web/proxy server Details USN-8398-1 fixed a vulnerability in nginx. The update caused a regression and was temporarily reverted in USN-8398-2. This update introduces a complete fix for CVE-2026-49975 . We apologize for the inconvenience. Original advisory details: It was discovered that nginx incorrectly handled certain cookie headers in the HTTP/2 implementation. A remote attacker could possibly use this issue to cause nginx to consume excessive resources, resulting in a denial of service. USN-8398-1 fixed a vulnerability in nginx. The update caused a regression and was temporarily reverted in USN-8398-2. This update introduces a complete fix for CVE-2026-49975 . We apologize for the inconvenience. Original advisory details: It was discovered that nginx incorrectly handled certain cookie headers in the HTTP/2 implementation. A remote attacker could possibly use this issue to cause nginx to consume excessive resources, resulting in a denial of service. Update instructions In general, a standard system update will make all the necessary changes. Learn more about how to get the fixes. The problem can be corrected by updating your system to the following package versions: Ubuntu Release Package Version 26.04 LTS resolute nginx – 1.28.3-2ubuntu1.5 nginx-core – 1.28.3-2ubuntu1.5 nginx-extras – 1.28.3-2ubuntu1.5 nginx-full – 1.28.3-2ubuntu1.5 nginx-light – 1.28.3-2ubuntu1.5 25.10 questing nginx – 1.28.0-6ubuntu1.7 nginx-core – 1.28.0-6ubuntu1.7 nginx-extras – 1.28.0-6ubuntu1.7 nginx-full – 1.28.0-6ubuntu1.7 nginx-light – 1.28.0-6ubuntu1.7 24.04 LTS noble nginx – 1.24.0-2ubuntu7.12 nginx-core – 1.24.0-2ubuntu7.12 nginx-extras – 1.24.0-2ubuntu7.12 nginx-full – 1.24.0-2ubuntu7.12 nginx-light – 1.24.0-2ubuntu7.12 22.04 LTS jammy nginx – 1.18.0-6ubuntu14.15 nginx-core – 1.18.0-6ubuntu14.15 nginx-extras – 1.18.0-6ubuntu14.15 nginx-full – 1.18.0-6ubuntu14.15 nginx-light – 1.18.0-6ubuntu14.15 Reduce your security exposure Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines. Get Ubuntu Pro References CVE-2026-49975 CVE-2026-49975 Related notices USN-8398-1 USN-8384-1 USN-8398-1 USN-8384-1