We posted an aside yesterday referencing Microsoft’s recent blog post for new security advisory 981374 referencing a new zero day vulnerability in Internet Explorer versions 6 and 7. New details have emerged since, and the exploit has moved from being what was described as part of “limited targeted attacks” to being widely accessible and available as a new module for the Metasploit framework.
Tag: "Remote Exploit"
Today is patch Tuesday for February 2010, and it marks a fairly busy patch cycle for Microsoft, who released thirteen updates today. In late January, there was an out-of-band release for two critical patches, in response to the high profile issue around the Internet Explorer Aurora exploit. This makes a total of fifteen total patches between since January’s patch Tuesday.
Back on November 11th, 2009 we confirmed Laurent Gaffié’s remote exploit for Windows that causes a kernel crash. The operating system actually freezes creating a denial of service when for example a user is tricked into clicking on a link to a malicious SMB share on a web page. The SMB client goes into an infinite loop when processing this malformed request according to Microsoft. The video below demonstrates this effect, having a user click a web site link and showing the crash.
We have noted some interesting responses since our post yesterday detailing the information in Juniper bulletin PSN-2010-01-623 and our thoughts on its somewhat understated effect. Since our post yesterday, the bulletin has been updated, becoming more specific about the versions affected (basically excluding JUNOS version 10.x and versions no longer supported by Juniper). We have tested all 256 permutations of the Options field in the TCP header, and reproduced the kernel crash, which is demonstrated in the video below.
A report has been received from Juniper at 4:25pm under bulletin PSN-2010-01-623 that a crafted malformed TCP field option in the TCP header of a packet will cause the JUNOS kernel to core (crash).
Python code was posted today by Laurent Gaffie on his blog, demonstrating a much too easy way to remotely crash a Windows 7 or Windows Server 2008 machine. The crash is caused by sending a NetBIOS header which specifies that the SMB packet is 4 bytes smaller or larger than it actually is. In this code sample below, you can see that the header has the length of the packet set to 9a rather than 9e (4 bytes smaller).