CVE-2006-5553: Cisco Security Agent (CSA) for Linux 4.5 before 4.5.1.657 and 5.0 before 5.0.0.193, as used by Unified Call...

Security readout for executives and security teams

This older Cisco issue can let a remote attacker make affected Cisco Security Agent for Linux systems consume resources and deny service. The cited description ties exposure to CSA deployments used with Cisco Unified CallManager and Unified Presence Server. No CVSS score is provided, so urgency depends on whether these legacy versions remain in use. Most likely exposure is legacy Cisco voice or presence infrastructure still running the named CSA for Linux versions, especially CUCM or CUPS environments. Modern environments are only exposed if this old agent or bundled platform remains deployed. Prioritize if legacy Cisco voice or presence systems remain business-critical or internet-adjacent. Without active exploitation evidence or CVSS data, this is not automatically a crisis, but unresolved exposure can still disrupt communications services. Mitigation focus: Check Cisco advisory for the official remediation path and applicability.; Upgrade CSA for Linux to 4.5.1.657, 5.0.0.193, or later where applicable.; Restrict network access to affected CUCM or CUPS systems to trusted administration paths..

Prepared

Jun 29, 2026, 09:39 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.