DNS Vulnerabilities

Impact

There are numerous vulnerabilities in Domain Name Servers (DNS) that are documented in the CERT Advisories. The two principal areas are:

Problems

BIND 4.9 releases prior to BIND 4.9.7 and BIND 8 releases prior to 8.1.2 do not properly bounds check a memory copy when responding to an inverse query request. An improperly or maliciously formatted inverse query on a TCP stream can crash the server or allow an attacker to gain root privileges.

BIND 4.9 releases prior to BIND 4.9.7 and BIND 8 releases prior to 8.1.2 do not properly bounds check many memory references in the server and the resolver. An improperly or maliciously formatted DNS message can cause the server to read from invalid memory locations, yielding garbage record data or crashing the server. Many DNS utilities that process DNS messages (e.g., dig, nslookup) also fail to do proper bounds checking. BIND 4.9 releases and BIND 8 release prior to 8.2.2 Patch 5 have a variety of security issues. You can review them and BIND Security.

Resolutions

The SARA test could not determine the version number of your DNS server. Contact your vendor to confirm that your DNS server is not vulnerable.