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