Cisco Security Advisory: Cisco IOS Malformed OSPF Packet Causes Reload Document ID: 61365 Revision 1.0 For Public Release 2004 August 18 15:00 UTC (GMT)
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Summary
A Cisco device running Internetwork Operating System (IOS) ® and enabled for the Open Shortest Path First (OSPF) protocol is vulnerable to a Denial of Service (DoS) attack from a malformed OSPF packet. The OSPF protocol is not enabled by default.
The vulnerability is only present in Cisco IOS release trains based on 12.0S, 12.2, and 12.3. Releases based on 12.0, 12.1 mainlines, and all Cisco IOS images prior to 12.0 are not affected.
Cisco has made free software available to address this vulnerability.
There are workarounds available to mitigate the effects.