Problem Description:
When named(8) receives a specially crafted dynamic update
message an internal assertion check is triggered which causes
named(8) to exit.
To trigger the problem, the dynamic update message must contains
a record of type "ANY" and at least one resource record set (RRset)
for this fully qualified domain name (FQDN) must exist on the
server.
Impact:
An attacker which can send DNS requests to a nameserver can cause
it to exit, thus creating a Denial of Service situation.
Workaround:
No generally applicable workaround is available, but some firewalls
may be able to prevent nsupdate DNS packets from reaching the
nameserver.
NOTE WELL: Merely configuring named(8) to ignore dynamic updates
is NOT sufficient to protect it from this vulnerability.