An posting in Threat post on a flaws that my blind severs: There is a critical vulnerability in several current versions of the BIND nameserver software that could allow an attacker to knock vulnerable DNS servers offline or compromise other applications running on those machines. The bug is present in several versions of the ubiquitous BIND software and the maintainers of the application have released a patch for it that they recommend users install as soon as possible.
The vulnerability is in BIND 9.7, 9.8, and 9.9 for Unix systems, but Windows versions are not affected. The problem lies in the way that the software handles certain regular expressions, and an attacker who exploits the vulnerability could not only cause a denial-of-service condition on the server but also could potentially compromise other software on the machine.
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