Description
Cisco IOS 12.0, 12.1, and 12.2, when GRE IP tunneling is used and the RFC2784 compliance fixes are missing, does not verify the offset field of a GRE packet during decapsulation, which leads to an integer overflow that references data from incorrect memory locations, which allows remote attackers to inject crafted packets into the routing queue, possibly bypassing intended router ACLs.
References
- ADV-2006-3502 vdb-entry
- 1016799 vdb-entry
- 28590 vdb-entry
- 20060906 Cisco IOS GRE issue mailing-list
- http://www.phenoelit.de/stuff/CiscoGRE.txt
- 21783 third-party-advisory
- 1526 third-party-advisory
- 19878 vdb-entry
- 20060906 Cisco IOS GRE Decapsulation Vulnerability vendor-advisory
- oval:org.mitre.oval:def:5713 vdb-entry signature
- cisco-ios-gre-acl-bypass(28786) vdb-entry