Vulnerability Note VU#472582

Cisco IOS IPv6 denial-of-service vulnerability

Original Release date: 26 Jan 2005 | Last revised: 01 Feb 2005


A vulnerability in the way Cisco IOS handles IPv6 packets could result in a remotely exploitable denial of service.


The Cisco Internetwork Operating System (IOS) includes support for processing Internet Protocol version 6 (IPv6) packets. A vulnerability in the way that IOS handles a sequence of specially crafted IPv6 packets could cause an affected device to reload (reboot), resulting in a denial of service. The specific nature of the crafted packets exploiting this vulnerability is not known. Only devices running IOS that have IPv6-configured interfaces, either physical or logical (e.g., tunnels), are vulnerable to this issue.


A remote attacker may be able to cause an affected device to reload, thereby creating a denial of service condition.



Cisco has addressed this issue in new versions of the IOS software. Please see Cisco's Security Advisory for more details.

Systems Affected (Learn More)

VendorStatusDate NotifiedDate Updated
Cisco Systems Inc.Affected-26 Jan 2005
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A N/A



Thanks to Cisco PSIRT for reporting this vulnerability.

This document was written by Chad R Dougherty.

Other Information

  • CVE IDs: Unknown
  • Date Public: 26 Jan 2005
  • Date First Published: 26 Jan 2005
  • Date Last Updated: 01 Feb 2005
  • Severity Metric: 10.61
  • Document Revision: 10


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