ADVISORIES | October 21, 2008

DNS TXT Record Parsing Bug in LibSPF2

By Dan Kaminsky

Reported: 10.20.08. Disclosed: 10.21.08. Researchers discovered a relatively common bug that parses TXT records delivered over DNS-dating back at least to 2002 in Sendmail 8.2.0 and almost certainly much earlier-in LibSPF2. This library retrieves Sender Policy Framework (SPF) records and applies policy according to those records. This implementation flaw allows for relatively flexible memory corruption and should be treated as a path to anonymous remote code execution.

Launch PDF

penetration testing

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