USN-8051-1: libssh vulnerabilities

USN-8051-1: libssh vulnerabilities

Publication date: 18 February 2026
Overview: Several security issues were fixed in libssh.

Packages
libssh - A tiny C SSH library

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)

Update instructions
The problem can be corrected by updating your system to the following package versions:

25.10 questing libssh-4 – 0.11.2-1ubuntu0.2
24.04 LTS noble libssh-4 – 0.10.6-2ubuntu0.3
22.04 LTS jammy libssh-4 – 0.9.6-2ubuntu0.22.04.6