CVE-2011-0413: DHCP May Crash After Processing a DHCPv6 Decline Message

AA-00456

DHCP May Crash After Processing a DHCPv6 Decline Message

Processing an address previously declined and tagged as abandoned can crash the server.
CERT: 
VU#686084
Document version: 
1.1
Posting date: 
26 Jan 2011
Program Impacted: 
DHCP
Versions affected: 
4.0.x-4.2.x
Severity: 
Medium
Exploitable: 
remotely
Description: 

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 http://nvd.nist.gov/cvss.cfm?calculator&adv&version=2

Workarounds: 

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.
Solution: 

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

Do you have Questions? Questions regarding this advisory should go to security-officer@isc.org.

This security advisory is a copy of the official document located on our website: https://www.isc.org/software/dhcp/advisories/cve-2011-0413

Do you need Software Support? Questions on ISC's Support services or other offerings should be sent to sales@isc.org. More information on ISC's support and other offerings are available at: http://www.isc.org/community/blog/201102/BIND-support

ISC Security Vulnerability Disclosure Policy: Details of our current security advisory policy and practice can be found here: https://www.isc.org/security-vulnerability-disclosure-policy