BIND -- Remote DOS

The Internet Systems Consortium reports:

Organizations across the Internet reported crashes interrupting
service on BIND 9 nameservers performing recursive queries.
Affected servers crashed after logging an error in query.c with
the following message: “INSIST(! dns_rdataset_isassociated(sigrdataset))”
Multiple versions were reported being affected, including all
currently supported release versions of ISC BIND 9.
Because it may be possible to trigger this bug even on networks
that do not allow untrusted users to access the recursive name
servers (perhaps via specially crafted e-mail messages, and/or
malicious web sites) it is recommended that ALL operators of
recursive name servers upgrade immediately.