The advisory comes almost immediately after H.D. Moore, a hacker and researcher who created the Metasploit vulnerability testing framework, published the attack code in two parts on Wednesday and late Thursday. The code was posted at several security mailing lists and at the Computer Academic Underground Web site.
According to the summary of the exploits, the first one enables a hacker to corrupt the cache in a DNS server. The other exploit is multifaceted and rotates, giving the attacker a shot at a larger amount of domain names through a single entry. Experts say the latter exploit could result in thousands of fake addresses inserted into a DNS server's cache.
In its latest bulletin, Microsoft noted that "attacks are likely imminent" because of the availability of exploit code.
"Since the coordinated release of these updates, the threat to DNS systems has increased due to a greater public understanding of the attacks, as well as detailed exploit code being published on the Internet," the advisory stated.
Reacting to the advisory, IT security pros are saying that Microsoft's statements vindicate the assertions of critics who thought the risk considerations regarding the DNS patch were underplayed.
"While Microsoft admits no active attacks on their radar, and they labeled the patch as 'important,' they are also subtlety saying that everyone needs to patch now because the risk is pretty large," said Andrew Storms, director of security for San Francisco-based nCircle, in an interview with Redmondmag.com on Friday.
IT security pros do admit that the DNS discourse and subsequent exploit release spiraled faster and further than Microsoft could have anticipated.
"The magnitude of the big-picture problem is probably more clear now than when Microsoft released the patch, especially now that exploit code is out and has the capability of significant disruption of all DNS-dependent network activity," said Don Leatham, director of solutions and strategy at Lumension Security in Scottsdale, Ariz.
Leatham suggested scrutiny of the fine print in Microsoft's latest DNS security bulletin.
"We've not seen an inordinate number of inquires on the installation issues. However people should pay special attention to the FAQ for this bulletin, as it has been updated multiple times as issues have been discovered."
While Microsoft touts its DNS vulnerability patch as a safe haven, there are still some issues with actually getting it installed in some Windows programs.
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