A vulnerability was found in the Bind DNS Server. Limits on simultaneous tcp connections have not been enforced correctly and could lead to exhaustion of file descriptors. In the worst case this could affect the file descriptors of the whole system.
For Debian 7 Wheezy, these problems have been fixed in version 1:9.8.4.dfsg.P1-6+nmu2+deb7u23.
We recommend that you upgrade your bind9 packages.
Further information about Extended LTS security advisories can be found at: https://deb.freexian.com/extended-lts/