CVE-2009-4920: Unspecified vulnerability in CTM on Cisco Adaptive Security Appliances (ASA) 5580 series devices with softw...

Security readout for executives and security teams

This CVE describes a remote denial-of-service condition affecting Cisco ASA 5580 firewalls running software 8.1(2). A large volume of small-packet traffic can trigger a watchdog traceback, potentially disrupting firewall availability. The public record does not provide CVSS, a detailed root cause, or confirmed exploitation. Exposure is likely limited to organizations still operating Cisco ASA 5580 series appliances with ASA software 8.1(2). Internet-facing or high-throughput perimeter deployments would carry more operational risk because the trigger is traffic volume related. Treat this as an availability risk for legacy perimeter firewalls. It does not indicate data theft or code execution, but a firewall outage can interrupt business connectivity. Prioritize if ASA 5580 devices remain in production, especially at internet edges. Mitigation focus: Inventory Cisco ASA 5580 appliances and identify any running ASA 8.1(2).; Review Cisco release notes for CSCsu11412 and vendor upgrade guidance.; Prioritize replacement or upgrade for exposed ASA 5580 perimeter devices..

Prepared

Jun 28, 2026, 02:01 UTC (UTC+00:00)

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