CVE-2016-9201: A vulnerability in the Zone-Based Firewall feature of Cisco IOS and Cisco IOS XE Software could allow an un...

Security readout for executives and security teams

This flaw could let traffic through Cisco IOS or IOS XE Zone-Based Firewall rules that were meant to block it. For an organization relying on those routers for segmentation or perimeter filtering, the business risk is loss of an expected security boundary. Exposure is limited to Cisco IOS or IOS XE devices using Zone-Based Firewall, especially release 15.3(3)M3 or other releases Cisco identifies in its advisory. Devices not using this feature are not shown as exposed by the provided sources. Prioritize remediation where Cisco routers enforce network boundaries. A bypass could undermine segmentation without needing authentication, but urgency should be based on actual ZBF deployment and whether affected releases are present. Mitigation focus: Review Cisco advisory cisco-sa-20161207-ios-zbf for exact affected trains.; Upgrade vulnerable devices to a Cisco-listed fixed release.; Prioritize devices enforcing perimeter, partner, or internal segmentation policy..

Prepared

Jun 13, 2026, 13:16 UTC (UTC+00:00)

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