Ubuntu Security Notices USN-8309-1 USN-8309-1: libssh2 vulnerability Publication date 26 May 2026 Overview libssh2 could be made to crash if it received specially crafted network traffic. Releases 26.04 LTS 25.10 24.04 LTS Open side navigation Close side navigation Packages Details Update instructions References Packages libssh2 - Client-side C library implementing the SSH2 protocol Details It was discovered that libssh2 incorrectly handled username and password length values during SSH password authentication. A remote attacker could possibly use this issue to cause a denial of service. It was discovered that libssh2 incorrectly handled username and password length values during SSH password authentication. A remote attacker could possibly use this issue to cause 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 libssh2-1t64 – 1.11.1-1ubuntu0.26.04.1 25.10 questing libssh2-1t64 – 1.11.1-1ubuntu0.25.10.1 24.04 LTS noble libssh2-1t64 – 1.11.0-4.1ubuntu0.24.04.1 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-2026-7598 CVE-2026-7598