CVE-2026-0966 Libssh: libssh: denial of service via zero-length input in ssh_get_hexa()

Description

A flaw was found in libssh. The API function `ssh_get_hexa()` is vulnerable to a denial of service when processing zero-length input. This can be exploited remotely by an attacker during GSSAPI (Generic Security Service Application Program Interface) authentication if the server's logging verbosity is set to `SSH_LOG_PACKET (3)` or higher. Successful exploitation could lead to a self-Denial of Service of the per-connection daemon process.

Exploitable remotely over the network, without an account and without any user action; an attacker can seriously compromise confidentiality, integrity or availability.

Attack vector

Network

Attack complexity

High

Privileges required

None

Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

Low

Availability

High

Affected products and versions