CVE-2007-0494: Denial of service via ANY query response containing multiple RRsets.


Verification logic for multiple DNSSEC RRsets can trigger server failure.

Posting date: 
30 Jan 2007
Program Impacted: 
Versions affected: 
9.0, 9.1, 9.2, 9.3.0-9.3.3, pre-release versions of 9.4.0, Alpha release of 9.5.0


When validating responses to type * (ANY) queries that return multiple RRsets in the answer section it is possible to trigger assertions checks. To be vulnerable you need to have enabled DNSSEC validation in named.conf by specifying trusted-keys.


Disable or restrict recursion (to limit exposure). Disable DNSSEC validation (remove all trusted-keys from named.conf).

Active exploits:

None known at this time.


Upgrade to BIND 9.2.8, BIND 9.3.4 or a released version of BIND 9.4 or 9.5


It is recommended that anyone using DNSSEC upgrade to BIND 9.3, as the DNSSEC implementation in BIND 9.2 has been obsoleted.

Related Documents:

See our BIND Security Matrix for a complete listing of Security Vulnerabilities and versions affected.  

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