CVE-2012-0383: Memory leak in the NAT feature in Cisco IOS 12.4, 15.0, and 15.1 allows remote attackers to cause a denial...

Security readout for executives and security teams

This is a denial-of-service issue in Cisco IOS NAT handling. A remote attacker could send SIP traffic that requires NAT translation and cause memory exhaustion, leading to a router hang or reload. The business impact is availability loss on affected network devices, not confirmed data theft. Exposure is most likely on Cisco IOS 12.4, 15.0, or 15.1 devices with NAT enabled where SIP packets are translated. The bundle does not identify specific platforms, configurations, or fixed releases. Treat this as a network availability risk. Prioritize internet-facing or voice-critical routers that translate SIP through NAT, then follow Cisco guidance for confirmed affected releases and remediation. Mitigation focus: Check Cisco advisory cisco-sa-20120328-nat for affected and fixed release guidance.; Inventory Cisco IOS 12.4, 15.0, and 15.1 devices using NAT.; Reduce unnecessary SIP translation exposure where operationally feasible..

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.