Description

A recently identified critical vulnerability in Cisco Unified Communications Manager (Unified CM) and Unified CM Session Management Edition (SME) puts organizations at risk of complete system compromise. Identified as CVE-2025-20309 and carrying the highest possible CVSS score of 10.0, this flaw enables unauthenticated remote attackers to obtain root access by exploiting static, hardcoded SSH credentials that were mistakenly included in production versions. The issue stems from fixed root account credentials meant only for development, which were mistakenly included in production releases. Since administrators are unable to modify or remove these credentials, the affected systems remain particularly exposed to security risks. BAn attacker can use this vulnerability to remotely access the system via SSH as the root user, enabling them to execute any command with full administrative rights. This serious flaw is identified as CWE-798: Use of Hard-coded Credentials. It was uncovered during Cisco's internal security assessments, and there have been no known instances of it being exploited in real-world scenarios. Cisco advises checking system logs for signs of unauthorized root logins via SSH. Cisco has issued free security updates and patches for the affected ES versions. Hardcoded credentials pose a serious supply-chain risk, bypassing all other authentication controls and being exploitable by anyone with network access.Immediate action is required to protect affected systems and avoid a complete compromise of the enterprise communications infrastructure.