CVE-2012-0387: Memory leak in the HTTP Inspection Engine feature in the Zone-Based Firewall in Cisco IOS 12.4, 15.0, 15.1,...

Security readout for executives and security teams

CVE-2012-0387 is a denial-of-service issue in Cisco IOS Zone-Based Firewall HTTP inspection. Crafted HTTP traffic passing through an affected device can consume memory and may cause a device reload, disrupting routing or firewall availability. Exposure is likely limited to Cisco IOS devices running the listed branches with Zone-Based Firewall HTTP Inspection Engine enabled and handling transit HTTP traffic. The source bundle does not provide precise fixed versions or configuration predicates. Treat as high priority where legacy Cisco IOS devices inspect transit HTTP at network boundaries. The business risk is availability loss, not data theft, but an affected edge device reload can interrupt critical connectivity. Mitigation focus: Review Cisco advisory cisco-sa-20120328-zbfw for fixed software and official mitigations.; Inventory Cisco IOS 12.4, 15.0, 15.1, and 15.2 devices using Zone-Based Firewall.; Prioritize internet-edge and high-availability transit devices with HTTP inspection enabled..

Prepared

Jun 24, 2026, 12:52 UTC (UTC+00:00)

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