Cisco has launched safety updates to handle 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 gadget as the foundation person, permitting them to realize 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 foundation account which are reserved to be used throughout improvement,” Cisco stated 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 enable the attacker to log in to the affected system and execute arbitrary instructions as the foundation person.”
Onerous-coded credentials like this normally come from testing or fast fixes throughout improvement, however they need to by no means make it into reside 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, eavesdrop on calls, or change how customers log in.
The networking gear main stated 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 via 15.0.1.13017-1, no matter gadget 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/lively/syslog/safe” for the foundation person with root permissions. The log can retrieved by working the under command from the command-line interface –
cucm1# file get activelog syslog/safe
The event comes merely days after the corporate fastened two safety flaws in Identification Companies Engine and ISE Passive Identification Connector (CVE-2025-20281 and CVE-2025-20282) that might allow an unauthenticated attacker to execute arbitrary instructions as the foundation person.