MaraDNS before 1.3.07.12 and 1.4.x before 1.4.08 computes hash values for DNS data without restricting the ability to trigger hash collisions predictably, which allows remote attackers to cause a denial of service (CPU consumption) by sending many crafted queries with the Recursion Desired (RD) bit set.

References

• https://nvd.nist.gov/vuln/detail/CVE-2012-0024
• https://bugzilla.redhat.com/show_bug.cgi?id=771428
• http://openwall.com/lists/oss-security/2012/01/03/13
• http://openwall.com/lists/oss-security/2012/01/03/6
• http://samiam.org/blog/20111229.html