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Cryptolocker Ransomware: What You Need To Know | Malwarebytes Unpacked

Cryptolocker Ransomware: What You Need To Know

Update 12/20/2013: A new version of Cryptolocker—dubbed Cryptolocker 2.0—has been discovered by ESET, although researchers believe it to be a copycat of the original Cryptolocker after noting large differences in the program’s code and operation. You can read the full blog comparing the two here.

Original story:

Just last month, antivirus companies  discovered a new ransomware known as Cryptolocker.

This ransomware is particularly nasty because infected users are in danger of losing their personal files forever.

cryptolocker

Spread through email attachments, this ransomware has been seen targeting companies through phishing attacks.

Cryptolocker will encrypt users’ files using asymmetric encryption, which requires both a public and private key.

The public key is used to encrypt and verify data, while private key is used for decryption, each the inverse of the other.

Below is an image from Microsoft depicting the process of asymmetric encryption.

assemcrypto

The bad news is decryption is impossible unless a user has the private key stored on the cybercriminals’ server.

Currently, infected users are instructed to pay $300 USD to receive this private key.

Infected users also have a time limit to send the payment. If this time elapses, the private key is destroyed, and your files may be lost forever.

Files targeted are those commonly found on most PCs today; a list of file extensions for targeted files include:
3fr, accdb, ai, arw, bay, cdr, cer, cr2, crt, crw, dbf, dcr, der, dng, doc, docm, docx, dwg, dxf, dxg, eps, erf, indd, jpe, jpg, kdc, mdb, mdf, mef, mrw, nef, nrw, odb, odm, odp, ods, odt, orf, p12, p7b, p7c, pdd, pef, pem, pfx, ppt, pptm, pptx, psd, pst, ptx, r3d, raf, raw, rtf, rw2, rwl, srf, srw, wb2, wpd, wps, xlk, xls, xlsb, xlsm, xlsx

In some cases, it may be possible to recover previous versions of the encrypted files using System Restore or other recovery software used to obtain “shadow copies” of files. The folks at BleepingComputer have some additional insight on this found here.

Removal:

Malwarebytes detects Cryptolocker infections as Trojan.Ransom, but it cannot recover your encrypted files due to the nature of asymmetric encryption, which requires a private key to decrypt files encrypted with the public key.

mbam-detect

In order to make removal even easier, a video was also created to guide users through the process (courtesy of Pieter Arntz).

While Malwarebytes cannot recover your encrypted files post-infection, we do have options to prevent infections before they start.

Users of Malwarebytes Anti-Malware Pro are protected by malware execution prevention and blocking of malware sites and servers.

To learn more on how Malwarebytes stops malware at its source, check out thisblog.

Free users will still be able to detect the malware if present on a PC, but will need to upgrade to Pro in order to access these additional protection options.

mbam-pro

Backup:

Also, the existence of malware such as Cryptolocker reinforces the need to back up your personal files.

However, a local backup may not be enough in some instances, as Cryptolocker may even go after backups located on a network drive connected to an infected PC.

Cloud-based backup solutions are advisable for business professionals and consumers alike. Malwarebytes offers Malwarebytes Secure Backup, which offers an added layer of protection by scanning every file before it is stored within the cloud in an encrypted format (don’t worry, you can decrypt these).

mbsb

To find out more on remove Cryptolocker, check out the official removal guide from Malwarebytes.

Update: Adam Kujawa from Malwarebytes gives further insight about Cryptolocker in an interview with Category 5

 

This article was sourced from: Cryptolocker Ransomware: What You Need To Know | Malwarebytes Unpacked.

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How to Diagnose a Computer Problem: 10 Quick Steps

computer diagnosis

How to Diagnose a Computer Problem
Edited by Cameron, Brandywine, R1zen187, Username152 and 11 others

Many people are faced with everyday computer problems that are easy to fix, but are unable to diagnose the actual problem. While there are many problems a computer will be faced with, this article will tell you where to look for common problems.

EditSteps
1Check the POST. POST stands for Power On Self Test. This is generally the first or second thing that appears on a computer after turning on the power. This appears before the operating system begins to load. The POST will display any problems found with hardware that makes the computer unable to boot, POST may also display problems with hardware that allow the computer to boot, but not operate at its full capacity during operation.

2Notice the load time of the OS (operating system). A longer than usual load time may indicate seek errors (or other errors) in the hard drive.
3Notice any graphics problems once the OS has loaded. Reduced graphics may indicate driver failures or hardware failures with graphic cards.
4Perform an auditory test. An auditory test is an unorthodox, but still effective way of judging how hard a computer is working. With the computer on and running, play any decent length audio file (usually above 30 secs). If the audio is choppy or slow, it usually means that the processor is working at an elevated level, or there is not enough RAM to run all programs loading. Changing the startup sound is a great way to apply this test. Another issue associated with choppy sounds is PIO (Programmed Input/Output) Mode. This affects how the hard drive reads and writes data from a drive. Switching to DMA allows for faster reads and writes, and can sometimes repair choppy audio.
5Check any newly installed hardware. Many operating systems, especially Windows, can conflict with new drivers. The driver may be badly written, or it may conflict with another process. Windows will usually notify you about devices that are causing a problem, or have a problem. To check this use the Device Manager, this can be accessed by entering the Control Panel, clicking the System icon, clicking the Hardware tab, and clicking on Device Manager. Use this to check and arrange the properties of hardware.
6Check any newly installed software. Software may require more resources than the system can provide. Chances are that if a problem begins after software starts, the software is causing it. If the problem appears directly upon startup, it may be caused by software that starts automatically on boot.
7Check RAM and CPU consumption. A common problem is a choppy or sluggish system. If a system is choppy it is good practice to see if a program is consuming more resources than the computer can provide. An easy way to check this is to use the Task Manager, right click on the taskbar select Task Manager, and click the Processes tab. The CPU column contains a number that indicates the percentage of CPU the process is consuming. The Mem Usage column indicates how much memory a process is consuming.
8Listen to the computer, if the hard drive is scratching or making loud noises, shut off the computer and have a professional diagnose the hard drive. Listen to the CPU fan, this comes on a high speed when the CPU is working hard, and can tell you when the computer is working beyond its capacity.
9Run a virus and malware scan. Performance problems can be caused by malware on the computer. Running a virus scan can unearth any problems. Use a commonly updated virus scanner (such as Norton Antivirus or Avast! Antivirus) and a commonly updated malware scanner (such as Spybot Search & Destroy).
10Check for the problem in safe mode. As a last ditch effort, check the problem in safe mode. To enter safe mode, tap F8 repeatedly during POST (this works on most systems). If the problem persists in safe mode, it is a fair bet that the operating system itself is to blame.

This article was taken from the following site: http://www.wikihow.com/Diagnose-a-Computer-Problem

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