Cisco’s Backdoor Blunder: Another Hardcoded Account Bites the Dust!
Cisco’s Unified Communications Manager had a backdoor account granting remote attackers root access. Rated as a maximum severity vulnerability, it required an upgrade to eliminate. Static user credentials meant for testing were the culprit. The only fix? Upgrading to the latest version. Remember, even tech giants occasionally leave the backdoor open!

Hot Take:
Well, well, well, looks like Cisco’s Unified Communications Manager was playing host to an uninvited guest: the infamous backdoor account. It’s always fun when your telephony system doubles as an open house for hackers. But hey, at least now Cisco’s Unified CM won’t be moonlighting as a speakeasy for cybercriminals. Let’s hope this is the last ‘oopsie’ in Cisco’s seemingly never-ending series of backdoor slip-ups!
Key Points:
- Cisco’s Unified Communications Manager had a backdoor account vulnerability.
- The vulnerability, CVE-2025-20309, was rated maximum severity.
- Fixing the issue requires upgrading to Cisco Unified CM 15SU3 or applying a specific patch.
- No current exploitation in the wild, but indicators of compromise and logging are available.
- This isn’t Cisco’s first rodeo with backdoor accounts in their products.