And if you want to do serious testing, then you can test your Antivirus on an actual malware. So, today I will discuss here a free website which lets you download virus sample on your PC for free to test Antivirus. The website that I will introduce her calls itself VXvault and you can download the latest virus sample from it. Reasons for testing anti-virus software Obviously, there is considerable intellectual justification for testing anti-virus software against real viruses. If you are an anti-virus vendor, then you do this (or should do it!) before every release of your product, in order to ensure that it really works. Over the past few months, one of the most dangerous viruses affecting computers has been Cryptolocker. Once infected, the virus encrypts all of the document files on your PC, and then demands payment (usually by Bitcoin) in order to divulge the necessary decryption key. While it's possible to remove the virus with standard antivirus software, and thus stop the infection spreading any further. Cryptolocker ransomware download – Where does CryptoLocker come from? CryptoLocker infected computers with an existing botnet, via harmful email attachments. The trojan encrypted files stored on local or mounted network drives. Since it wasn’t a virus, it didn’t spread across your network on its own.

• Download Cryptolocker Virus For Testing Sites
• Download Cryptolocker Virus For Testing Tool

Anti Malware Testfile

Additional notes:

1. This file used to be named ducklin.htm or ducklin-html.htm or similar based on its original author Paul Ducklin and was made in cooperation with CARO.
2. The definition of the file has been refined 1 May 2003 by Eddy Willems in cooperation with all vendors.
3. The content of this documentation (title-only) was adapted 1 September 2006 to add verification of the activity of anti-malware or anti-spyware products. It was decided not to change the file itself for backward-compatibility reasons.

Who needs the Anti-Malware Testfile

(read the complete text, it contains important information)
Version of 7 September 2006

If you are active in the anti-virus research field, then you will regularly receive requests for virus samples. Some requests are easy to deal with: they come from fellow-researchers whom you know well, and whom you trust. Using strong encryption, you can send them what they have asked for by almost any medium (including across the Internet) without any real risk.

Other requests come from people you have never heard from before. There are relatively few laws (though some countries do have them) preventing the secure exchange of viruses between consenting individuals, though it is clearly irresponsible for you simply to make viruses available to anyone who asks. Your best response to a request from an unknown person is simply to decline politely.

A third set of requests come from exactly the people you might think would be least likely to want viruses „users of anti-virus software“. They want some way of checking that they have deployed their software correctly, or of deliberately generating a „virus incident in order to test their corporate procedures, or of showing others in the organisation what they would see if they were hit by a virus“.

Reasons for testing anti-virus software

Obviously, there is considerable intellectual justification for testing anti-virus software against real viruses. If you are an anti-virus vendor, then you do this (or should do it!) before every release of your product, in order to ensure that it really works. However, you do not (or should not!) perform your tests in a „real“ environment. You use (or should use!) a secure, controlled and independent laboratory environment within which your virus collection is maintained.

Using real viruses for testing in the real world is rather like setting fire to the dustbin in your office to see whether the smoke detector is working. Such a test will give meaningful results, but with unappealing, unacceptable risks.

Since it is unacceptable for you to send out real viruses for test or demonstration purposes, you need a file that can safely be passed around and which is obviously non-viral, but which your anti-virus software will react to as if it were a virus.

If your test file is a program, then it should also produce sensible results if it is executed. Also, because you probably want to avoid shipping a pseudo-viral file along with your anti-virus product, your test file should be short and simple, so that your customers can easily create copies of it for themselves.

The good news is that such a test file already exists. A number of anti-virus researchers have already worked together to produce a file that their (and many other) products „detect“ as if it were a virus.

Agreeing on one file for such purposes simplifies matters for users: in the past, most vendors had their own pseudo-viral test files which their product would react to, but which other products would ignore.

The Anti-Malware Testfile

This test file has been provided to EICAR for distribution as the „EICAR Standard Anti-Virus Test File“, and it satisfies all the criteria listed above. It is safe to pass around, because it is not a virus, and does not include any fragments of viral code. Most products react to it as if it were a virus (though they typically report it with an obvious name, such as „EICAR-AV-Test“).

The file is a legitimate DOS program, and produces sensible results when run (it prints the message „EICAR-STANDARD-ANTIVIRUS-TEST-FILE!“).

It is also short and simple – in fact, it consists entirely of printable ASCII characters, so that it can easily be created with a regular text editor. Any anti-virus product that supports the EICAR test file should detect it in any file providing that the file starts with the following 68 characters, and is exactly 68 bytes long:

X5O!P%@AP[4PZX54(P^)7CC)7}$EICAR-STANDARD-ANTIVIRUS-TEST-FILE!$H+H*

The first 68 characters is the known string. It may be optionally appended by any combination of whitespace characters with the total file length not exceeding 128 characters. The only whitespace characters allowed are the space character, tab, LF, CR, CTRL-Z. To keep things simple the file uses only upper case letters, digits and punctuation marks, and does not include spaces. The only thing to watch out for when typing in the test file is that the third character is the capital letter „O“, not the digit zero.

You are encouraged to make use of the EICAR test file. If you are aware of people who are looking for real viruses „for test purposes“, bring the test file to their attention. If you are aware of people who are discussing the possibility of an industry-standard test file, tell them about www.eicar.org, and point them at this article.

In order to facilitate various scenarios, we provide 4 files for download. The first, eicar.com, contains the ASCII string as described above. The second file, eicar.com.txt, is a copy of this file with a different filename. Some readers reported problems when downloading the first file, which can be circumvented when using the second version. Just download and rename the file to „eicar.com“. That will do the trick. The third version contains the test file inside a zip archive. A good anti-virus scanner will spot a ‚virus‘ inside an archive. The last version is a zip archive containing the third file. This file can be used to see whether the virus scanner checks archives more than only one level deep.

Once downloaded run your AV scanner. It should detect at least the file „eicar.com“. Good scanners will detect the ‚virus‘ in the single zip archive and may be even in the double zip archive. Once detected the scanner might not allow you any access to the file(s) anymore. You might not even be allowed by the scanner to delete these files. This is caused by the scanner which puts the file into quarantaine. The test file will be treated just like any other real virus infected file. Read the user’s manual of your AV scanner what to do or contact the vendor/manufacturer of your AV scanner.

IMPORTANT NOTE
EICAR cannot be held responsible when these files or your AV scanner in combination with these files cause any damage to your computer. YOU DOWNLOAD THESE FILES AT YOUR OWN RISK. Download these files only if you are sufficiently secure in the usage of your AV scanner. EICAR cannot and will not provide any help to remove these files from your computer. Please contact the manufacturer/vendor of your AV scanner to seek such help.

How to delete the test file from your PC

We understand (from the many emails we receive) that it might be difficult for you to delete the test file from your PC. After all, your scanner believes it is a virus infected file and does not allow you to access it anymore. At this point we must refer to our standard answer concerning support for the test file. We are sorry to tell you that EICAR cannot and will not provide AV scanner specific support. The best source to get such information from is the vendor of the tool which you purchased.

Please contact the support people of your vendor. They have the required expertise to help you in the usage of the tool. Needless to say that you should have read the user’s manual first before contacting them.

What is CryptoLocker?

CryptoLocker is by now a well known piece of malware that can be especially damaging for any data-driven organization. Once the code has been executed, it encrypts files on desktops and network shares and “holds them for ransom”, prompting any user that tries to open the file to pay a fee to decrypt them. For this reason, CryptoLocker and its variants have come to be known as “ransomware.”

Malware like CryptoLocker can enter a protected network through many vectors, including email, file sharing sites, and downloads. New variants have successfully eluded anti-virus and firewall technologies, and it’s reasonable to expect that more will continue to emerge that are able to bypass preventative measures. In addition to limiting the scope of what an infected host can corrupt through buttressing access controls, detective and corrective controls are recommended as a next line of defense.

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FYI, this article is CryptoLocker specific. If you’re interested in reading about ransomware in general, we’ve written A Complete Guide To Ransomware that is very in-depth.

Update September 2018: Ransomware attacks have decreased significantly since their peak in 2017. CryptoLocker and it’s variants are no longer in wide distribution, and new ransomware has taken over. Ransomware has evolved as more of a targeted attack instead of the previous wide distribution model, and is still a threat to businesses and government entities.

What Does CryptoLocker Do?

On execution, CryptoLocker begins to scan mapped network drives that the host is connected to for folders and documents (see affected file-types), and renames and encrypts those that it has permission to modify, as determined by the credentials of the user who executes the code.

CryptoLocker uses an RSA 2048-bit key to encrypt the files, and renames the files by appending an extension, such as, .encrypted or .cryptolocker or .[7 random characters], depending on the variant. Finally, the malware creates a file in each affected directory linking to a web page with decryption instructions that require the user to make a payment (e.g. via bitcoin). Instruction file names are typically DECRYPT_INSTRUCTION.txt or DECRYPT_INSTRUCTIONS.html.

As new variants are uncovered, information will be added to the Varonis Connect discussion on Ransomware. For example, a variant known as “CTB-Locker” creates a single file in the directory where it first begins to encrypt files, named, !Decrypt-All-Files-[RANDOM 7 chars].TXT or !Decrypt-All-Files-[RANDOM 7 chars].BMP.

How to Prevent CryptoLocker

The more files a user account has access to, the more damage malware can inflict. Restricting access is therefore a prudent course of action, as it will limit the scope of what can be encrypted. In addition to offering a line of defense for malware, it will mitigate potential exposure to other attacks from both internal and external actors.

While getting to a least privilege model is not a quick fix, it’s possible to reduce exposure quickly by removing unnecessary global access groups from access control lists. Groups like “Everyone,” “Authenticated Users,” and “Domain Users,” when used on data containers (like folders and SharePoint sites) can expose entire hierarchies to all users in a company. In addition to being easy targets for theft or misuse, these exposed data sets are very likely to be damaged in a malware attack. On file servers, these folders are known as “open shares,” if both file system and sharing permissions are accessible via a global access group.

Although it’s easiest to use technologies designed to find and eliminate global access groups, it is possible to spot open shares by creating a user with no group memberships, and using that account’s credentials to “scan” the file sharing environment. For example, even basic net commands from a windows cmd shell can be used to enumerate and test shares for accessibility:

• • net view (enumerates nearby hosts)
  • net view host (enumerates shares)
  • net use X: hostshare (maps a drive to the share)
  • dir /s (enumerates all the files readable by the user under the share)

These commands can be easily combined in a batch script to identify widely accessible folders and files. Remediating these without automation, unfortunately, can be a time-consuming and risky endeavor, as it’s easy to affect normal business activity if you’re not careful. If you uncover a large amount of accessible folders, consider an automated solution. Automated solutions can also help you go farther than eliminating global access, making it possible to achieve a true least-privilege model and eliminate manual, ineffective access-control management at the same time.

How to Detect CryptoLocker

If file access activity is being monitored on affected files servers, these behaviors generate very large numbers of open, modify, and create events at a very rapid pace, and are fairly easy to spot with automation, providing a valuable detective control. For example, if a single user account modifies 100 files within a minute, it’s a good bet something automated is going on. Configure your monitoring solution to trigger an alert when this behavior is observed. Varonis DatAlert monitors and tracks file system behavior for ransomware attacks out-of-the-box. There is no need for extra configuration if Varonis is monitoring your data.

If you don’t have an automated solution to monitor file access activity, you may be forced to enable native auditing. Native auditing, unfortunately, taxes monitored systems and the output is difficult to decipher. Instead of attempting to enable and collect native audit logs on each system, prioritize particularly sensitive areas and consider setting up a file share honeypot.

A file share honeypot is an accessible file share that contains files that look normal or valuable, but in reality are fake. As no legitimate user activity should be associated with a honeypot file share, any activity observed should be scrutinized carefully. If you’re stuck with manual methods, you’ll need to enable native auditing to record access activity, and create a script to alert you when events are written to the security event log (e.g. using dumpel.exe).

If you’re PowerShell inclined, we’ve written a bit on how to combat CryptoLocker with PowerShell.

If your detective control mechanism can trigger an automated response, such as disabling the user account, the attack is effectively stopped before inflicting further damage. For example, a response to a user that generates more than 100 modify events within a minute might include:

• Notifying IT and security administrators (include the affected username and machine)
• Checking the machine’s registry for known keys/values that CryptoLocker creates:
  • Get-Item HKCU:SoftwareCryptoLockerFiles).GetValueNames()
• if value exists, disable user automatically.

If recorded access activity is preserved and adequately searchable, it becomes invaluable in recovery efforts, as it provides a complete record of all affected files, user accounts, and (potentially) hosts. Varonis customers can use the output from report 1a (as described here) to restore files from a backup or shadow copy.

Depending on the variant of CryptoLocker, encryption may be reversible with a real-time disassembler.

Ransomware Safety Tips

Download Cryptolocker Virus For Testing Sites

• Update your antivirus and endpoint protection software – these solutions can help detect certain types of ransomware and prevent it from encrypting your files.
• Avoid phishing scams – phishing emails are the most prevalent delivery mechanism for ransomware.
• Keep backups of your documents – it’s much faster and easier to recover your documents from a backup than it is to decrypt them, if they’ve been compromised in a ransomware attack.
• Commit to a zero-trust/least privilege model – ransomware can only affect the folders a user can write to. A least privilege model limits that access to only what’s absolutely necessary.
• Monitor file activity and user behavior to detect, alert and respond to potential ransomware activity.

Download Cryptolocker Virus For Testing Tool

New ransomware variants are popping up all the time – luckily our dedicated security forensics team does the legwork for you and diligently updates the ransomware signatures that Varonis detects. See how it works with a free 1:1 demo and learn more about how our ransomware defense architecture is designed to protect enterprise data from zero-day attacks beyond the endpoint – catching ransomware that traditional perimeter security doesn’t see.