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CVE-2011-0413: DHCP May Crash After Processing a DHCPv6 Decline Message
Author: Michael McNally Reference Number: AA-00456 Views: 26185 Created: 2011-09-09 23:16 Last Updated: 2012-06-08 14:07 0 Rating/ Voters

DHCP May Crash After Processing a DHCPv6 Decline Message

Processing an address previously declined and tagged as abandoned can crash the server.
Document version: 
Posting date: 
26 Jan 2011
Program Impacted: 
Versions affected: 

When the DHCPv6 server code processes a message for an address that was previously declined and internally tagged as abandoned it can trigger an assert failure resulting in the server crashing. This could be used to crash DHCPv6 servers remotely. This issue only affects DHCPv6 servers. DHCPv4 servers are unaffected.

CVSS Score: 6.1 (AV:A/AC:L/Au:N/C:N/I:N/A:C)

For more information on CVSS scores, visit


There is no direct workaround.

Exposure to the vulnerability can be limited by a review of the filters and access to the DHCP server. It is highly recommended to limit access to those devices which require DHCP server, management access, and systems monitoring.

Active exploits: 
None known at this time.

Upgrade to 4.1.2-P1, 4.1-ESV-R1, or 4.2.1b1

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