This advisory covers five distinct vulnerabilities in libssh: CVE-2026-0964 (improper sanitation of paths from SCP servers), CVE-2026-0965 (denial of service via improper configuration file handling), CVE-2026-0966 (buffer underflow in ssh_get_hexa() on invalid input), CVE-2026-0967 (denial of service via inefficient regular expression processing), and CVE-2026-0968 (denial of service due to malformed SFTP message). These vulnerabilities can lead to information disclosure, integrity and availability impacts. The issues have been fixed by rebasing libssh to version 0.12.0 in Red Hat Enterprise Linux 10 and its Extended Update Support releases. The advisory rates the overall impact as moderate.

The vulnerabilities collectively can result in limited confidentiality and integrity loss, and denial of service conditions. Specifically, improper input handling and sanitation could allow attackers to cause buffer underflows or disrupt service availability. The CVSS vector for CVE-2026-0964 indicates network attack vector with high attack complexity and required user interaction, resulting in low confidentiality, integrity, and availability impacts. No known exploits in the wild have been reported.

Red Hat has released updated libssh packages (version 0.12.0-2.el10) for Red Hat Enterprise Linux 10 and its Extended Update Support variants that address these vulnerabilities. Users should apply these official updates promptly following Red Hat's guidance at https://access.redhat.com/articles/11258. No additional mitigation steps are indicated beyond applying the vendor-provided patches.