The Barracuda Labs Internet Security Blog

Posted by: Barracuda Labs

Earlier today, malicious links that claimed to offer videos and pictures of Erin Andrews began appearing on Twitter. Search terms leading to these malicious tweets include the following:

erin andrews peephole video link rapidshare
espn reporter erin andrews
erin andrews peephole pictures
erin andrews video torrent
erin andrews hot pics

The malicious tweets were (automatically) created using numerous accounts and the Twitter API; the links have been shortened using bit.ly, as shown in the following screenshot.

If the the user clicks on one of the links, the following series of redirections occur:

hxxp://bit.ly/1bkUV9
-> hxxp://xombag.com/video/go.php?sid=2&name=erin+andrews+hot+pics&theme
=trends&hostingtype=twitter

-> hxxp://sunny-tube-world.com/xplays.php?id=40014&name=erin+andrews+hot+pics&the
me=trends&hostingtype=twitter

The name parameter in the above URLs corresponds to the text of the tweet that started the chain, which allows the operators of the propagation campaign to determine which combinations of terms (listed at the beginning of this post) made the best lures. The series of redirects ends at the page shown in the screenshot below, which offers a fake video that the user will likely assume is of Erin Andrews.

The fake video, served via hxxp://newfileexe.com/onlinemovies.40014.exe, is a trojan downloader– a small piece of malware that (when executed) will download and execute other malicious programs. AV detections for this instance are practically non-existent:

http://www.virustotal.com/analisis/f9e4218db68f661751ffe2ced790ebf30e55e8bb7
a39fc46e47831453d214e8f-1248216878

One of the most fascinating parts of this campaign is how the trojan downloader retrieves additional malware. Instead of downloading executables, the downloader fetches the following image files:

hxxp://isyouimageshere.com/item/b6bc3e14a0639460413e87d5c4d82e8267c6a66
1217f2f1530b599dd6f76ee1d23103cd88fd83fc10/b4a0d091c46/titem.gif

hxxp://imgesinstudioonline.com/perce/861c5e6420337400215e97e5c4d81e42b74

62631f1af8f65702579fdbff64e4d03a0ac38ef284f117/d40040b1148/qwerce.gif

hxxp://yourimagesstudio.com/werber/d4300051f41/217.gif

Hidden inside these viewable GIF files (as comment blocks) are encrypted malware executables. After retrieving the files, the downloader extracts the comments, transforms them back into malware, and executes them.

Users of the PWSS are protected from this threat.

Posted by: Barracuda Labs

With the release of Windows 7 only months away, it is worthwhile to begin considering its expected impact on security. This post reasons about a few of the changes the new operating system’s (eventual) widespread adoption will bring.

Application vulnerabilities will be harder to weaponize into working exploits. While Windows memory protections such as DEP and ASLR have been around for several years, ubiquitous applications (IE8, Firefox 3) and their corresponding plugins (Flash, Acrobat Reader, and QuickTime) are now using them. When these protections are combined with recent fixes by Microsoft that address the few corner cases in which they were disabled, the result is that often, even if a vulnerability exists, successfully exploiting it may not be possible. As an example, the Firefox 3.5 just-in-time compiler vulnerability has been reported to not to work under Windows Vista or Windows 7. In the long term, the adoption of these technologies may cause criminals to shift their focus from attacks that are technical in nature (i.e., attacking the browser or its plugins) to those that are social in nature (as used by Rogue AV).

Hardware-assisted rootkits such as Blue Pill will be difficult to deploy. Rootkits that use hardware virtualization operate outside of the host operating system by first assuming a special privilege level, called VMX root mode. Given that Windows 7 implements Windows XP Mode (XPM) using hardware virtualization extensions (and therefore runs in VMX root mode), hardware-assisted rootkit installation becomes considerably more complex. Such a rootkit would need to overcome significant technical hurdles to avoid crashing the OS or alerting the user, which include bypassing OS protection mechanisms, saving XPM guest state, cleanly disabling VMX root mode in the host, and providing emulation services so that XPM applications will continue functioning.

Malware will face significant challenges in evading modern forms of dynamic analysis. Next-generation malware analysis approaches (e.g., Ether) introspect the behavior of malicious software through the use of hardware virtualization extensions. As it is very difficult to reliably detect the presence of an external malware analyzer that resides inside a such hypervisor, some criminals have instead responded by creating malware that refuses to run if it detects the presence of hardware-assisted virtualization. However, given Windows 7’s use of hardware-assisted virtualization in the implementation of XPM, malware that employs this crude form of detection will preclude itself from the very end users it intended to target.

In summary, the release of Windows 7 looks to be an all-around win for security; its adoption will benefit both end users and security professionals.

Posted by: Barracuda Labs

After months of inactivity, Waledac has begun a new propagation email campaign. Messages in this run all relate to the July 4th holiday; an example is shown below.

From: Elmer Curry < tonya.galati@nextiraone.fr >
Date: Sat, 4 Jul 2009 04:37:49
Subject: Happy Birthday, America!
To: < redacted >@orange.fr

Well done 4th! hxxp://axkgi.fireworksnetwork.com/

Similar to Storm’s 2008 July 4th email campaign, clicking on the above link will take the user to a fake YouTube page claiming to offer a video of an expensive fireworks display:

The “video” is actually Waledac malware, which will infect the user’s system if they attempt to “view” it. AV detections for these instances are poor:

http://www.virustotal.com/analisis/7e288c3f5a0d3adee8b50d249fb3a65
6e0ca3736437a16abf4abbbf54af73931-1246683971

Users of the PWSS are protected from this campaign.