Exclusive - Ssh20cisco125 Vulnerability

On , Cisco released an advisory detailing a maximum severity vulnerability (CVE-2025-20309) in Cisco Unified Communications Manager (CUCM) and Unified Communications Manager SME. The vulnerability stems from hard-coded root SSH credentials that cannot be changed or removed by the administrator.

. Specifically, it stems from a flaw in how the SSH server parses malformed or unexpected channel request messages before a user has successfully logged in. 2. Attack Vector Remote, unauthenticated. ssh20cisco125 vulnerability exclusive

[ ssh20 ] + [ cisco ] + [ 125 ] | | | Protocol Target OS Privilege/ (SSHv2.0) Developer Target Identifier On , Cisco released an advisory detailing a

In this vulnerability, however, the authentication mechanism fails to properly validate certain crafted inputs. An attacker can and still be granted access. By submitting specially crafted input during the SSH authentication phase, the attacker can trick the ASA software into believing the authentication was successful, even though the private key was never used. Specifically, it stems from a flaw in how

Cisco strongly recommends the following steps to remediate exposure: Software Updates

Enter your OS version (e.g., IOS XE 17.x or ASA 9.x) to see all applicable security advisories.