CVE-2007-5537: Cisco Unified Callmanager

High severity, CVSS 7.8. EPSS: 2% chance of exploitation in the next 30 days.

Cisco Unified Communications Manager (CUCM, formerly CallManager) 5.1 before 5.1(2), and Unified CallManager 5.0, allow remote attackers to cause a denial of service (kernel panic) via a flood of SIP INVITE messages to UDP port 5060, which triggers resource exhaustion, aka CSCsi75822.

Affected products

• Cisco Unified Callmanager: version 5.0 only
• Cisco Unified Communications Manager: up to and including 5.1\(2\)

Published 2007-10-18. Last modified 2026-06-16.