Microsoft Internet Explorer 6 drops DNS pins based on failed connections to irrelevant TCP ports, which makes it easier for remote attackers to conduct DNS…

Microsoft Internet Explorer 6 drops DNS pins based on failed connections to irrelevant TCP ports, which makes it easier for remote attackers to conduct DNS rebinding attacks, as demonstrated by a port 81 URL in an IMG SRC, when the DNS pin had been established for a session on port 80, a different issue than CVE-2006-4560.