This affects 2008 and newer, older versions did not support DNAME[1] records. It isn&#x27;t clear whether an existing DNAME record needs to exist in order for this to be exploitable. Skimming the Sonar FDNS[2] dataset, only 5,581 DNAME records were identified[3]. A diff has been posted by Greg Linares[4], showing the addition of a memset(0) to the DNAME merge function.<p>1. <a href="https:&#x2F;&#x2F;tools.ietf.org&#x2F;html&#x2F;rfc6672" rel="nofollow">https:&#x2F;&#x2F;tools.ietf.org&#x2F;html&#x2F;rfc6672</a>
2. <a href="https:&#x2F;&#x2F;scans.io&#x2F;study&#x2F;sonar.fdns" rel="nofollow">https:&#x2F;&#x2F;scans.io&#x2F;study&#x2F;sonar.fdns</a>
3. <a href="https:&#x2F;&#x2F;hdm.io&#x2F;data&#x2F;20151121_dname.txt.gz" rel="nofollow">https:&#x2F;&#x2F;hdm.io&#x2F;data&#x2F;20151121_dname.txt.gz</a>
4. <a href="https:&#x2F;&#x2F;twitter.com&#x2F;Laughing_Mantis&#x2F;status&#x2F;674308454379425792" rel="nofollow">https:&#x2F;&#x2F;twitter.com&#x2F;Laughing_Mantis&#x2F;status&#x2F;67430845437942579...</a>