Cisco has launched safety updates to deal with a maximum-severity safety 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 prone system 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 because of the presence of static person credentials for the basis account which might be reserved to be used throughout improvement,” Cisco mentioned in an advisory launched Wednesday.
“An attacker may exploit this vulnerability by utilizing the account to log in to an affected system. A profitable exploit may permit the attacker to log in to the affected system and execute arbitrary instructions as the basis person.”
Hardcoded credentials like this often come from testing or fast fixes throughout improvement, however they need to by no means make it into stay techniques. 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 inner safety testing.
CVE-2025-20309 impacts Unified CM and Unified CM SME variations 15.0.1.13010-1 by means of 15.0.1.13017-1, no matter system configuration.
Cisco has additionally launched indicators of compromise (IoCs) related to the flaw, stating profitable exploitation would lead to a log entry to “/var/log/lively/syslog/safe” for the basis person with root permissions. The log can retrieved by working the beneath command from the command-line interface –
cucm1# file get activelog syslog/safe
The event comes merely days after the corporate mounted two safety 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.
