BleepingComputer.com: Trojan Virus problem SHeur3. AQRA

My computer is totally infected with a virus that i just cant get rid of....Its a trojan horse SHeur3.AQRA.. Win32/Zbot.A...and VBS/Generic..Its totally flooored my system, cant do anything on it (
The only anti virus i had was AVG freeware, but it seems to be getting swamped and cant cope.
Anyone any ideas how to remove it from my computer ?

This post has been edited by hamluis: 17 October 2010 - 05:01 PM
Reason for edit: Moved from XP forum to Am I Infected ~ Hamluis.

I'm afraid I have very bad news.

Win32/Zbot, SHeur3.AQRA and VBS Generic are names used by AVG (see the link for Threat aliases below) for variants of Win32/Ramnit.A, a file infector with IRCBot functionality which infects .exe, and .HTML/HTM files, and opens a back door that compromises your computer. Using this backdoor, a remote attacker can access and instruct the infected computer to download and execute more malicious files. The infected .HTML or .HTM files may be detected as Virus:VBS/Ramnit.A or VBS/Generic. Win32/Ramnit.A!dll is a related file infector often seen with this infection. It too has IRCBot functionality which infects .exe, .dll and .HTML/HTM files and opens a back door that compromises your computer. This component is injected into the default web browser by Worm:Win32/Ramnit.A which is dropped by a Ramnit infected executable file.

-- Note: As with most malware infections, the threat name may be different depending on the anti-virus or anti-malware program which detected it. Each security vendor uses their own naming conventions to identify various types of malware.

• Understanding virus names
  
• Threat aliases for W32/Ramnit.a!35B43CB537D0
  
• Threat aliases for W32/Ramnit.a!5343A023502C

With this particular infection the safest solution and only sure way to remove it effectively is to reformat and reinstall the OS.

Why? The malware injects code in legitimate files similar to the Virut virus and in many cases the infected files (which could number in the thousands) cannot be disinfected properly by your anti-virus. When disinfection is attempted, the files often become corrupted and the system may become unstable or irreparable. The longer Ramnit.A remains on a computer, the more files it infects and corrupts so the degree of damage can vary.

Ramnit is commonly spread via a flash drive (usb, pen, thumb, jump) infection where it copies Worm:Win32/Ramnit.A with a random file name. The infection is often contracted by visiting remote, crack and keygen sites. These type of sites are infested with a smörgåsbord of malware and a major source of system infection.

In my opinion, Ramnit.A is not effectively disinfectable, so your best option is to perform a full reformat as there is no guarantee this infection can be completely removed. In most instances it may have caused so much damage to your system files that it cannot be completely cleaned or repaired. Security vendors that claim to be able to remove file infectors cannot guarantee that all traces of it will be removed as they may not find all the remnants. If something goes awry during the malware removal process there is always a risk the computer may become unstable or unbootable and you could loose access to all your data.

Further, your machine has likely been compromised by the backdoor Trojan and there is no way to be sure the computer can ever be trusted again. It is dangerous and incorrect to assume the computer is secure even if your anti-virus reports that the malware appears to have been removed.

Many experts in the security community believe that once infected with this type of malware, the best course of action is to wipe the drive clean, reformat and reinstall the OS. Please read:

• When should I re-format? How should I reinstall?
  
• Where to draw the line? When to recommend a format and reinstall?

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Backdoors and What They Mean to You

This is what Jesper M. Johansson at Microsoft TechNet has to say: Help: I Got Hacked. Now What Do I Do?.

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Important Note:: If your computer was used for online banking, has credit card information or other sensitive data on it, you should disconnect from the Internet until your system is cleaned. All passwords should be changed immediately to to include those used for banking, email, eBay, paypal and any online activities which require a username and password. You should consider them to be compromised. You should change each password using a clean computer and not the infected one. If not, an attacker may get the new passwords and transaction information. Banking and credit card institutions should be notified of the possible security breach. Failure to notify your financial institution and local law enforcement can result in refusal to reimburse funds lost due to fraud or similar criminal activity.

This post has been edited by quietman7: 18 October 2010 - 09:29 AM

Wow...even worse than i thought
Thank you for the reply quietman7, really apprciate it. I will change my banking details here on my laptop now. As to reformating, i dont have the experience to do that, or a new operating system to put onto my computer even if i did. My computer did not come with a disc, but with the operating system already installed.
Looks like it is a goner and i may just have to buy a new one.
Thanks for your help.

You're welcome.

Sorry the news was not promising in your case.

If you're not sure how to reformat or need help with reformatting, please review:

• How to partition and format a hard disk in Windows XP
  
• Prepping for a Clean Install Windows XP

These links include specific step-by-step instructions with screenshots:

• XP Clean Install Interactive Setup
  
• Reformat and Install of Windows

Vista users can refer to these instructions:

• Windows Vista Clean Install
  
• How to Do a Clean Install and Setup with a Full Version of Vista
  
• How to Do a Clean Install with a Upgrade Version of Vista

Windows 7 users can refer to these instructions:

• How to Do a Clean Installation with Windows 7
  
• Windows 7 Clean Install Screens

Don't forget you will have to go to Microsoft Update and apply all Windows security patches after reformatting.

Note: If you're using an IBM, Sony, HP, Compaq, Toshiba, Gateway or Dell machine, you may not have an original CD Disk. By policy Microsoft no longer allows OEM manufactures to include the original Windows XP CD-ROM on computers sold with Windows preinstalled. Instead, most computers manufactured and sold by OEM vendors come with a vendor-specific Recovery Disk or Recovery Partition for performing a clean "factory restore" that will reformat your hard drive, remove all data and restore the computer to the state it was in when you first purchased it. Also be sure to read Technology Advisory Recovery Media. If the recovery partition has become infected, you will need to contact the manufacturer, explain what happened and ask them to send full recovery disks to use instead. If you lost or misplaced your recover disks, again you can contact and advise the manufacturer. In many cases they will send replacements as part of their support.

If you have made a disk image with an imaging tool (i.e. Acronis True Image, Drive Image, Ghost, Macrium Reflect, etc.) before your system was infected, then using it is another option. Disk Imaging allows you to take a complete snapshot (image) of your hard disk which can be used for system recovery in case of a hard disk disaster or malware resistent to disinfection. The image is an exact, byte-by-byte copy of an entire hard drive (partition or logical disk) which can be used to restore your system at a later time to the exact same state the system was when you imaged the disk or partition. Essentially, it will restore the computer to the state it was in when the image was made. You will then have to reinstall all programs that you added afterwards. This includes all security updates and patches from Microsoft.

If you need additional assistance with reformatting or partitioning if you decide to try that, you can start a new topic in the Operating Systems Subforums forum.


Caution: If you are considering backing up data and reformatting or doing a factory restore with a vendor-specific Recovery Disk/Recovery Partition due to malware infection, keep in mind with file infectors, there is always a chance of backed up data reinfecting your system. If the data is that important to you, then you can try to salvage some of it but there is no guarantee so be forewarned that you may have to start over again afterwards if reinfected by attempting to recover your data. Only back up your important documents, personal data files, photos to a CD or DVD drive, not a flash drive or external hard drive as they may become compromised in the process. The safest practice is not to backup any executable files (*.exe), screensavers (*.scr), dynamic link library (*.dll), autorun (*.ini) or script files (.php, .asp, .htm, .html, .xml) files because they may be infected by malware. Avoid backing up compressed files (.zip, .cab, .rar) that have executables inside them as some types of malware can penetrate compressed files and infect the .exe files within them. Other types of malware may even disguise itself by hiding a file extension or adding to the existing extension as shown here (click Figure 1 to enlarge) so be sure you look closely at the full file name. If you cannot see the file extension, you may need to reconfigure Windows to show file name extensions. Then make sure you scan the backed up data with your anti-virus prior to to copying it back to your hard drive.

If your CD/DVD drive is unusable, another word of caution if you are considering backing up to an external usb hard drive as your only alternative. External drives are more susceptible to infection and can become compromised in the process of backing up data. I'm not saying you should not try using such devices but I want to make you aware of all your options and associated risks so you can make an informed decision if its worth that risk.

• How and Where to backup your files in XP or Vista
  
• How to Backup and Restore in Windows 7
  
• How to use Ubuntu Live CD to Backup Files from your dead Windows Computer

Again, do not back up any files with the following file extensions: exe, .scr, .dll, .ini, .htm, .html, .php, .asp, .xml, .zip, .rar, .cab as they may be infected.

Important: Since many file infectors are spread by using infected removable usb flash drives and external drives, before starting the backup and restore process you should disable autorun. Why? This type of infection usually involves malware that modifies/loads an autorun.inf (text-based configuration) file into the root folder of all drives (internal, external, removable) along with a malicious executable. When removable media is inserted (mounted), autorun looks for autorun.inf and automatically executes the malicious file to run silently on your computer.

Keeping autorun enabled on USB (pen, thumb, jump) and other removable drives has become a significant security risk due to the increasing number of malware variants that can infect them and transfer the infection to your computer. To learn more about this risk, please read:

• When is AUTORUN.INF really an AUTORUN.INF?
  
• Nick Brown's blog: Memory stick worms
  
• USB-Based Malware Attacks
  
• Danger USB! Worm targets removable memory sticks

Many security experts recommend you disable Autorun as a method of prevention. Microsoft recommends doing the same.

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Microsoft Security Advisory (967940): Update for Windows Autorun