USN-8051-1 fixed vulnerabilities in libssh. This update provides the corresponding updates for Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, and Ubuntu 20.04 LTS. Original advisory details: It was discovered that libssh clients incorrectly handled the key exchange process. A remote attacker could possibly use this issue to cause libssh clients to crash, resulting in a denial of service. (CVE-2025-8277) It was discovered that the libssh SCP client incorrectly sanitized paths received from servers. A remote attacker could use this issue to cause libssh SCP clients to overwrite files outside of the working directory and possibly execute arbitrary code. (CVE-2026-0964) It was discovered that libssh incorrectly handled parsing configuration files. A local attacker could possibly use this issue to cause libssh to access non-regular files, resulting in a denial of service. (CVE-2026-0965) It was discovered that libssh incorrectly handled the ssh_get_hexa() function. A remote attacker could possibly use this issue to cause libssh to crash, resulting in a denial of service. (CVE-2026-0966) It was discovered that libssh incorrectly handled certain regular expressions. A local attacker could possibly use this issue to cause libssh to consume resources, resulting in a denial of service. (CVE-2026-0967) It was discovered that the libssh SFTP client incorrectly handled certain malformed longname fields. A remote attacker could use this issue to cause libssh SFTP clients to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2026-0968)