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Trojan

Sep 29 2009   12:58AM GMT

New IRS Scam and It Could Cost You More Than Taxes!



Posted by: Ken Harthun
Security, IRS Phishing, E-mail scam, Social Engineering, keylogger, data stealer, Trojan

You usually see this around tax season, but it seems the cyber-crooks have figured out that fear of the IRS is an evergreen topic.

US-CERT is aware of public reports of malicious code circulating via spam email messages related to the IRS. The attacks arrive via an unsolicited email message and may contain a subject line of “Notice of Underreported  Income.” These messages may contain a link or attachment. If users click on this link or open the attachment, they may be infected with malicious code, including the Zeus Trojan.

The Zeus Trojan is a keylogger that steals sensitive data, especially targeting online banking credentials. According to “New IRS Scam E-mail Could Be Costly”, in Brian Krebs’ Security Fix column, Landfill Service Corp. (LSC), a solid waste company based in Apalachin, NY is a recent victim of the Trojan. The firm may end up losing at least $92,000 from the incident. Not good.

The Zeus keystroke logging Trojan’s engine is a file called “sdra64.exe.” At least that’s what LSC’s tech guy found (Variations are sure to surface).

Rather than repeat it in my own words, here’s the US-CERT list of recommendations:

Aug 31 2009   10:40PM GMT

Have You Noticed? Phishing Attacks Are Down



Posted by: Ken Harthun
insecure, Security, Phishing, Malware, Social Engineering, Secure Computing, Trojan

It’s just not in fashion anymore; phishing attacks are ‘way down, falling out of favor with cybercriminals who now prefer malicious websites and password-stealing Trojan horse programs.

IBM’s security research and development division, X-Force, recently issued a report that found throughout 2008 , phishing volume was around 0.5 percent of overall spam volume. But in the first half of 2009, the volume of phishing attacks fell to around 0.1 percent of spam volume. Not only did the volume of phishing attacks drop, but the targets also changed: in 2008, 90 percent of all phishing attacks targeted the financial industry; in the first half of 2009, that percentage had dropped to 66 percent.

That’s the good news. The bad news is that, according to the report, the number of malicious Web links is up 508 percent in the first half of 2009 and many of these links appear on otherwise trusted sites such as search engines. X-Force Director Kris Lamb says, “There is no such thing as safe browsing today and it is no longer the case that only the red light district sites are responsible for malware. We’ve reached a tipping point where every Web site should be viewed as suspicious and every user is at risk."

A copy of the IBM report can be downloaded here (PDF).

As always, let the surfer beware.


Jan 30 2009   4:23AM GMT

“Victim” of Cybercrime Found Searching for Illegal Porn



Posted by: Ken Harthun
Malware, Cybercrime, Anti-malware, Trojan

Talk about irony. You get infected by a cybercriminal’s illegal bot (Ozdok/Mega-D in this case) which takes a screen shot that shows you searching for illegal underage porn; then, security researchers get hold of some screen shots from the bot’s command and control (C&C) server; while going through the shots, the researchers come across those of your screen and notify the authorities (presumably, the FBI).

From a Security Works research note, Ozdok: Watching the Watchers:

Also, a note to the gentleman searching for images of nude preteen girls: You can run all the anti-spyware tools you can find, and employ the best anonymity tools in your web browser - it’s not going to help you if you get infected with an advanced trojan like Ozdok/Mega-D or one of the many others that allow hackers to take screenshots of your computer desktop. Don’t worry though, you probably won’t need a computer in the near term, as we’ve notified the authorities of your name and location (which you conveniently provided in a series of screenshots).

The good news is that you can remove the pest. Here’s what Symantec recommends for their products:

The following instructions pertain to all current and recent Symantec antivirus products, including the Symantec AntiVirus and Norton AntiVirus product lines.

1. Disable System Restore (Windows Me/XP).
2. Update the virus definitions.
3. Run a full system scan.
4. Delete any values added to the registry.

Complete removal instructions in this article.


Nov 30 2008   4:21PM GMT

An MBR Tool to Combat Mebroot



Posted by: Ken Harthun
Security, Malware, Virus, Anti-virus, Rootkit, Anti-malware, Trojan

Assuming you or your client is not already infected with Mebroot, there’s another tool you can use to easily recover in the event of an infection: MBRtool 2.3 from DIY DataRecovery.

MRBTool is a freeware DOS program designed to backup, restore, and manipulate your hard disk MBR. The latest version includes a boot disk builder that will allow you to create a diskette or bootable CD/DVD, making it ideal for recovering from a Mebroot infection. If you are sure the target machine is clean, or you have a clean image that you can restore, you simply use MBRTool to make a backup of the valid MBR. In the event of infection, use the boot disk to start the machine and restore the valid MBR. Bye, Bye, Mebroot!

Going beyond simple recovery, you could use MBRTool to make a copy of and examine an infected MBR to compare its code against known Mebroot variants. But, be careful: you don’t want that infected MBR to get away from you.


Nov 25 2008   10:11PM GMT

Phony Security Software Cleared from 1 Million PCs



Posted by: Ken Harthun
Security, Cybercrime, Malware, Anti-malware, Trojan, Scam

According to Microsoft, the November release of its Malicious Software Removal Tool (MSRT) removed the phony security software, Win32/FakeSecSen, from 994,061 distinct machines in just nine days: MSRT Review on Win32/FakeSecSen Rogues. Win32/FakeSecSen is a family of programs that claim to scan for malware and display fake warnings of “malicious programs and viruses”. These programs attempt to force users to pay to remove the “threats” they found. Some of them attempt (illegally) to look official by impersonating Microsoft products using names such as “Antivirus XP”, “AntivirusXP 2008”, “WinDefender 2008”, “XP Antivirus”, or similar.

My experience with a couple of these rogues has shown that they are relatively easy to remove. Microsoft’s Windows Defender and Malware Bytes’ Anti-Malware both do a good job of removing the pest.


Nov 20 2008   5:41PM GMT

Super-Trojan Sinowal/Mebroot: Seven Ways to Protect Yourself



Posted by: Ken Harthun
Security, Microsoft Windows, Vulnerabilities, Cybercrime, Malware, Rootkit, Trojan

Sinowal, also known as “Mebroot” and “Torpig” to various antivirus companies, is a dangerous rootkit that uses the computer’s Master Boot Record (MBR) as its Auto-Start Entry Point (ASEP). The Trojan typically infects Windows XP PCs via malicious websites using code that exploits vulnerabilities in Adobe Reader, Flash Player, or Apple QuickTime–vulnerabilities that have already been patched. Once the Trojan gets on your system, it does an interesting little dance to prevent detection. Windows Secrets writer Woody Leonhard describes Sinowal’s stealthy behavior in his November 20, 2008 article, “Don’t be a victim of Sinowal - the super-Trojan:”

“The key to Sinowal/Mebroot’s ’success’ is that it’s so sneaky and is able to accomplish its dirty work in many different ways. How sneaky? Consider this: Sinowal/Mebroot doesn’t run straight out to your MBR and overwrite it. Instead, the Trojan waits for 8 minutes before it even begins to analyze your computer and change the Registry. Digging into the MBR doesn’t start until 10 minutes after that.

“Sinowal/Mebroot erases all of its tracks and then reboots the PC using the adulterated MBR and new Registry settings 42 minutes into the process.”

Also contributing to the Trojan’s effectiveness is that it’s constantly changing. Washington Post journalist Brian Krebs posted a chilling overview of Sinowal’s criminal mischief in his October 31, 2008 column, “Virtual Heist Nets 500,000+ Bank, Credit Accounts:”

“Sinowal…constantly morphs its appearance to slip past security software. Between April and October, researchers spotted an average of 60 to 80 new Sinowal variants per month…

“On Oct. 21, a new Sinowal variant was submitted to Virustotal.com, which scans incoming files against nearly three dozen commercial anti-virus programs and maintains a historical record of those results. Only 10 out of 35 of those security programs - or 28.5 percent - identified it as such or even flagged it as suspicious.”

Very scary, but here are seven things you can do to protect yourself:

  1. Apply all security patches to Windows XP.
  2. Apply all patches to third-party software, particularly Adobe Reader, Flash Player, and Apple QuickTime. These are the main avenues of infection.
  3. Make sure your antivirus detection definitions are up to date.
  4. Create a limited user account and use it to browse the web.
  5. Only visit websites you trust.
  6. Run your browser in a sandbox.
  7. Switch to Vista–it’s not currently vulnerable.

As always, constant vigilance is necessary on the Wild, Wild, Web.


Oct 17 2008   1:26AM GMT

Beware of E-Mail Scam Targeting Microsoft Customers



Posted by: Ken Harthun
Security, spam, email, Email security, Trojan, E-mail scam

The latest e-mail scam targeting Microsoft customers delivers the Backdoor:Win32/Haxdoor trojan as an attachment. The email looks like this:

Dear Microsoft Customer,

Please notice that Microsoft company has recently issued a Security Update for OS Microsoft Windows. The update applies to the following OS versions: Microsoft Windows 98, Microsoft Windows 2000, Microsoft Windows Millenium, Microsoft Windows XP, Microsoft Windows Vista.

Please notice, that present update applies to high-priority updates category. In order to help protect your computer against security threats and performance problems, we strongly recommend you to install this update.

Since public distribution of this Update through the official website http://www.microsoft.com would have result in efficient creation of a malicious software, we made a decision to issue an experimental private version of an update for all Microsoft Windows OS users.

As your computer is set to receive notifications when new updates are available, you have received this notice.

In order to start the update, please follow the step-by-step instruction:
1. Run the file, that you have received along with this message.
2. Carefully follow all the instructions you see on the screen.

If nothing changes after you have run the file, probably in the settings of your OS you have an indication to run all the updates at a background routine. In that case, at this point the upgrade of your OS will be finished.

We apologize for any inconvenience this back order may be causing you.

Thank you,

Steve Lipner
Director of Security Assurance
Microsoft Corp.

Anyone reading this can spot the obvious grammar and punctuation mistakes, the first things that should alert them that this is a scam. But, as we know, users blindly click on anything and everything, especially links in official-looking messages.

Please advise your users to immediately delete this message if they receive it, and continue to advise them to NEVER click a link or open an email that they are not sure about. It’s better to err on the side of caution.

By the way, Consumer Reports has an Online Security Guide posted on their website. It’s well worth looking at and certainly good for your non-savvy users as it’s written for, well, consumers.


Sep 21 2008   5:10PM GMT

Beware of the Fake Video Codec Malware Trick



Posted by: Ken Harthun
Security, Cybercrime, Social Engineering, Malware, Trojan

A variant of Win32/Zlob is being spread by cybercriminals via the fake video codec trick. Through misdirection or outright deception (including social engineering), users are sent to a site that has what appears to be embedded video. When they arrive at the page, there’s a message in the viewer similar to the one shown at “The ZLOB Show: Trojan Poses as Fake Video Codec, Loads More Threats.” If the user falls for the trick, Zlob trojan is downloaded and installed.

The variant, posing as “MediaTubeCodec.1.220.2.exe”–a name that should arouse suspicion in savvy users, but probably looks “official” to the unenlightened–was recently analyzed by Microsoft (see “Another Reason to Avoid Piracy” in their Microsoft Malware Protection Center blog). Microsoft updated its detection signatures to detect this variant as TrojanDownloader:Win32/Zlob.gen!CD. If diagnostics on a user’s PC (netstat, for example) reveal connections to any of the following, assume infection and take appropriate action:

  • hxxp://64.247.39.247
  • hxxp://second-reason.com
  • hxxp://viacodecright2.com

According to the blog, “Only the first two are responding at the time of writing—both appear to be running nginx [pronounced "engine X"] (a lightweight web/mail server), one server is hosted in the USA and the other in China. So please folks—avoid piracy, and be wary when a website insists that you download a new codec in order to watch a video or listen to a song.”


Sep 12 2008   2:22AM GMT

Bootable Thumb Drive Virus Scanner Saves the Day



Posted by: Ken Harthun
Security, Linux, Hacking, Malware, Anti-virus, Anti-malware, Trojan

Forgive me if I brag a bit in this post, but I think I earned the right. You be the judge.

Last weekend, I noticed strange behavior on my home system. ESET Smart Security kept reporting that it had “found and quarantined m.exe, probably a variant of Win.Qhost trojan.” Every time I plugged in a USB thumb drive, ESET would pop up with the message. I couldn’t run HijackThis. If I tried to go to certain antivirus websites–Avira in particular–my browser closed. Sysinternals Process Explorer wouldn’t run. My thumb drive showed two hidden files: Autorun.inf and m.exe. Hmmm. Running ipconfig /displaydns revealed multiple connections to porn and malware sites. Searching Google led me to some tools that eventually fixed my problem at home. Turns out I had a bigger problem.

Apparently, I had picked up the infection from a client’s Exchange server and during my weekly tour there, I found that the tools I used on my XP machine wouldn’t run on Windows Server 2003.  I tried everything in my arsenal; no tool found anything wrong. This thing was very stealthy; even Safe Mode didn’t disable it. I was about to give up. Then I remembered that I’d recently finished making up a bootable Linux thumb drive virus scanner using the AntiVir rescue CD, a tool that allows offline scanning (thank you, Avira, you made it a little easier for me). I booted the server to the thumb drive, ran the scan, rebooted the server, and voila! The infection was gone.

There’s a whole backstory to this incident that I won’t bore you with. Suffice it to say that I’m glad I put in the hours of hacking and research to come up with a really useful tool that I was able to use to help a client. Veni! Vidi! Vici!