CVE-2005-3774: Cisco PIX 6.3 and 7.0 allows remote attackers to cause a denial of service (blocked new connections) via sp...

Security readout for executives and security teams

This is an old denial-of-service issue in Cisco PIX 6.3 and 7.0. A remote attacker could send spoofed TCP traffic that consumes connection-tracking state, causing the firewall to block new legitimate connections. The business impact is service disruption, not disclosed data theft or code execution. Exposure is most likely where legacy Cisco PIX firewalls running 6.3 or 7.0 still protect reachable networks, especially with external interfaces processing untrusted TCP traffic. The bundle does not identify affected configurations beyond Cisco PIX 6.3 and 7.0. Treat as a legacy infrastructure resilience risk. It is not KEV-listed and has no CVSS in the bundle, but any remaining affected PIX firewall could become a network choke point during targeted disruption. Mitigation focus: Inventory for Cisco PIX devices running 6.3 or 7.0.; Review Cisco’s advisory and response before applying version or configuration changes.; Prioritize vendor-supported upgrade, replacement, or retirement for remaining legacy PIX deployments..

Prepared

Jun 29, 2026, 16:32 UTC (UTC+00:00)

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