Cisco has launched security updates to handle a maximum-severity security flaw in Unified Communications Supervisor (Unified CM) and Unified Communications Supervisor Session Administration Version (Unified CM SME) that might allow an attacker to login to a inclined machine as the basis person, permitting them to achieve elevated privileges.
The vulnerability, tracked as CVE-2025-20309, carries a CVSS rating of 10.0.
“This vulnerability is as a result of presence of static person credentials for the basis account which might be reserved to be used throughout growth,” Cisco mentioned in an advisory launched Wednesday.
“An attacker might exploit this vulnerability through the use of the account to log in to an affected system. A profitable exploit might permit the attacker to log in to the affected system and execute arbitrary instructions as the basis person.”
Hardcoded credentials like this normally come from testing or fast fixes throughout growth, however they need to by no means make it into dwell programs. In instruments like Unified CM that deal with voice calls and communication throughout an organization, root entry can let attackers transfer deeper into the community, pay attention to calls, or change how customers log in.
The networking tools main mentioned it discovered no proof of the flaw being exploited within the wild, and that it was found throughout inside security testing.
CVE-2025-20309 impacts Unified CM and Unified CM SME variations 15.0.1.13010-1 via 15.0.1.13017-1, regardless of machine configuration.
Cisco has additionally launched indicators of compromise (IoCs) related to the flaw, stating profitable exploitation would end in a log entry to “/var/log/energetic/syslog/safe” for the basis person with root permissions. The log can retrieved by operating the under command from the command-line interface –
cucm1# file get activelog syslog/safe
The event comes merely days after the corporate mounted two security flaws in Id Companies Engine and ISE Passive Id Connector (CVE-2025-20281 and CVE-2025-20282) that might allow an unauthenticated attacker to execute arbitrary instructions as the basis person.
