Remove Silasw9pa .Crinf Ransomware and Restore Your Files

Several ransomware variants have been known to decrypt more and more user files lately. The ransomware itself and is also known as DecryptorMax or CryptInfinite. This devastating cyber-threat to user PCs has proven that it can be quite effective by encrypting important user files and scarring users that their keys for decryption will be deleted in 24 hours, making it impossible for them to decrypt their files. However, security experts strongly advise users to never pay the ransom and fund the cybercriminals to continue and enhance their ransomware campaigns. Also, there are several methods by which some .crinf files may be decrypted, mentioned after this article.

Name.Crinf Ransomware Trojan
TypeRansomware Trojan
Short DescriptionThe virus is known to execute administrrative commands and encrypt user data to extort the user for funds.
SymptomsThe user may have his wallpaper changed with ransom instructions and see his files encrypted and unable to be opened with the .crinf browser extension.
Distribution MethodMalicious web links or infected email attachments.
Detection ToolDownload Malware Removal Tool, to See If Your System Has Been Affected by .Crinf Ransomware Trojan
User ExperienceJoin our forum to read on how to decrypt your files and discuss.Crinf Ransomware.
Data Recovery ToolWindows Data Recovery by Stellar Phoenix Notice! This product scans your drive sectors to recover lost files and it may not recover 100% of the encrypted files, but only few of them, depending on the situation and whether or not you have reformatted your drive.

.Crinf Ransomware – How Did I Get It

One way to be infected by this nasty online threat is by simply visiting the wrong website or being redirected to it. This may happen if you clicked on a malicious URL in a comment, message. Users also report being redirected by having adware programs on their computers that display pop-ups and other adverts to such malicious online locations.

The other way that this ransowmare may get into user PCs and the most widely used one is by email. Some users report receiving messages on websites such as Craigslist with attached .doc files with random names such as 28312-d21.docx, for example. These infected attachments may either have additional file of the following formats – .exe, .bat, .tmp, .dll or they may have modified macros that create exploits and let the actual trojan penetrate the defences of the user PC.

Either way, security experts advise users to use external mail management software such as Mozilla Thunderbird or Microsoft Outlook, for example. It is also highly recommended not to open attachments in messages from external websites that have private messaging mode. In case you do not have any other choice, an advanced anti-malware tool is recommended that has an active protection, blocking out the incoming intrusions.

.Crinf Ransomware – What Does It Do

This particular type of ransomware has been analysed by information security experts to perform the following activities once activated on a compromised system

First, it generates a victim identifier or unique number to ID the specific PC being infected. It does it by making a malicious .exe file that has a unique set of numbers and digits with symbols as well on it. The .exe is usually stored in the %User Files% directory.

The .crinf malware then takes advantage of the windows command prompt to input these commands in order to delete File History (Shadow Volume Copies) so that affected users do not have backup of their encrypted data:

cmd.exe /k vssadmin.exe Delete Shadows /All /Quiet
cmd.exe /k bcdedit.exe /set {default} recoveryenabled No
cmd.exe /k bcdedit.exe /set {default} bootstatuspolicy ignoreallfailures

Additionally the abovewritten commands use bootstatuspolicy in order to disable the Windows Startup Repair. The good news is that these commands require to run as Administrator so you may be notified a request to run them.

After doing the following this malware may also kill some processes while it analyses the files it wants to decrypt.
According to malware experts at BleepingComputer.com this usually happens by entering the following commands:

TASKKILL /F /IM msconfig.exe
TASKKILL /F /IM rstrui.exe
TASKKILL /F /IM tcpview.exe
TASKKILL /F /IM procexp.exe
TASKKILL /F /IM procmon.exe
TASKKILL /F /IM regmon.exe
TASKKILL /F /IM wireshark.exe
TASKKILL /F /IM LordPE.exe
TASKKILL /F /IM regedit.exe
TASKKILL /F /IM cmd.exe
TASKKILL /F /IM filemon.exe
TASKKILL /F /IM procexp64.exe

After the questionable malware has scanned for files to encrypt, it begins the encryption process.
It crawls through all the drive letters to encrypt files containing any of the following extensions:

*.ACCDB, *.BAY, *.DBF, *.DER, *.DNG, *.DOCX, *.DXF, *.ERF, *.INDD, *.MEF, *.MRW, *.ODB, *.ODP, *.PDD, *.PEF, *.PPTM, *.PSD, *.PTX, *.RAW, *.SRF, *.XLK, *.XLS, *.ach, *.aiff, *.arw, *.asf, *.asx, *.avi, *.back, *.backup, *.bak, *.bin, *.blend, *.cdr, *.cer, *.cpp, *.crt, *.crw, *.dat, *.dcr, *.dds, *.des, *.dit, *.doc, *.docm, *.dtd, *.dwg, *.dxg, *.edb, *.eml, *.eps, *.fla, *.flac, *.flvv, *.gif, *.groups, *.hdd, *.hpp, *.iif, *.java, *.kdc, *.key, *.kwm, *.log, *.lua, *.m2ts, *.max, *.mdb, *.mdf, *.mkv, *.mov, *.mpeg, *.mpg, *.msg, *.ndf, *.nef, *.nrw, *.nvram, *.oab, *.obj, *.odc, *.odm, *.ods, *.odt, *.ogg, *.orf, *.ost, *.pab, *.pas, *.pct, *.pdb, *.pdf, *.pem, *.pfx, *.pif, *.png, *.pps, *.ppt, *.pptx, *.prf, *.pst, *.pwm, *.qba, *.qbb, *.qbm, *.qbr, *.qbw, *.qbx, *.qby, *.qcow, *.qcow2, *.qed, *.raf, *.rtf, *.rvt, *.rwl, *.safe, *.sav, *.sql, *.srt, *.srw, *.stm, *.svg, *.swf, *.tex, *.tga, *.thm, *.tlg, *.vbox, *.vdi, *.vhd, *.vhdx, *.vmdk, *.vmsd, *.vmx, *.vmxf, *.vob, *.wav, *.wma, *.wmv, *.wpd, *.wps, *.xlr, *.xlsb, *.xlsm, *.xlsx, *.yuv,*.JPEG,*.jpe, *.jpg

After a file has been encrypted, it may look the following way – /Filename/.jpg.crinf or simply /filename/.crinf.

When it encrypts files with the .crinf extension at the end of it, the malware may exclude any other files conatining the following strings-Windows, Program Files, KEY, .crinf

Whilst it is conducting the encryption process, the trojan may add a registry value for each of the filles that are under the key “HKCU\Software\CryptInfinite”:

For example, if the files contain the following names:

HKCU\Software\CryptInfinite\Files\11
C:\Users\Public\Pictures\Sample Pictures\DSC21983.jpg
HKCU\Software\CryptInfinite\Files\12
C:\Users\Public\Pictures\Sample Pictures\DSC21234983.jpg
HKCU\Software\CryptInfinite\Files\13
C:\Users\Public\Pictures\Sample Pictures\DSC21454564983.jpg
HKCU\Software\CryptInfinite\Files\14
C:\Users\Public\Pictures\Sample Pictures\DSC21342983.jpg
HKCU\Software\CryptInfinite\Files\15
C:\Users\Public\Pictures\Sample Pictures\DSC21983.jpg
HKCU\Software\CryptInfinite\Files\16
C:\Users\Public\Pictures\Sample Pictures\DSC21912312383.jpg
HKCU\Software\CryptInfinite\Files\17
C:\Users\Public\Pictures\Sample Pictures\DSC2146983.jpg

The ransomware trojan may also add additional information in Windows Registry Editor to this very same registry key. Its final stage is to change the desktop wallpaper in order to display a ransom note and hence automatically start its executables by adding the usual HKEY_LOCAL_USER Run key in it.

The ransomware may also add the following keys with different values:

HKCU\Software\CryptInfinite
HKCU\Software\CryptInfinite\Files
HKCU\Software\CryptInfinite\Info
HKCU\Software\CryptInfinite\Info\KEY 000000
HKCU\Software\CryptInfinite\Info\1 000000
HKCU\Software\CryptInfinite\Info\c 23
HKCU\Software\CryptInfinite\Info\m 57
HKCU\Software\CryptInfinite\Info\s 21
HKCU\Software\CryptInfinite\Info\Finish True
HKCU\Software\Microsoft\Windows\CurrentVersion\Run\Microsoft corporation C:\Users\\USER-PCBCBE-F350.exe
HKCU\Control Panel\Desktop\WallpaperStyle “0”
HKCU\Control Panel\Desktop\Wallpaper “C:\Users\\z2.bmp”

Finally, the ransomware changes the user’s wallpaper to a ransom note message:

.crypt ransomware

The trojan also drops a file with the same ransom instructions. It is called ReadDecryptFilesHere.txt and it is dropped in every folder where encrypted files can be found.

This is the message viewed in both the wallpaper, the .txt document and the .exe software itself:

“Your personal files have been encrypted!
Your documents, photos, databases and other important files have been encrypted using a military grade encryption algorithm.
The only way to decrypt your files is with a unique decryption key stored remotely in our servers. All your files are now
unusable until you decrypt them. You have 24h to pay for the release of your decryption key. After 24h have passed, your
decryption key will be erased and you will never be able to restore your files.
To obtain your unique decryption key you will need to pay $500 using a PayPal MyCash voucher.
If the payment is not sent within 12h the amount to obtain your decryption key will be $1000.
PayPal MyCash vouchers can be purchased at CVS, 7-Eleven, Dollar General, fred`s Super Dollar,
Family Dollar and many other stores.
——————————————————————–
After obtaining your PayPal MyCash voucher code you need to send an email to
[email protected] with the following information.
1. Your $500 PayPal MyCash PIN
2. Your encryption ID =
Shortly after the voucher is received and verified, all your files will be restored to their previous state.
All payments are processed and verified manually, do not try to send invalid PIN numbers.”

Finally the user is being presented a user interface with the same message and ‘Next’ button featuring instructions on file decryption.

Remove .Crinf Ransomware Completely

In order to remove this ransomware it is important to act as if you remove any other trojan horse from your computer and isolate the threat first. Then, you should boot into safe mode and scan your computer with an advanced anti-malware program in order to remove the ransomware effectively since any PC infection is unique by itself.
Here are instructions on getting rid of this ransomware. Bear in mind that you should back up your encrypted files first since you will be attempting to decrypt them later:

1. Boot Your PC In Safe Mode to isolate and remove .Crinf Ransomware Trojan
2. Remove .Crinf Ransomware Trojan with SpyHunter Anti-Malware Tool
3. Remove .Crinf Ransomware Trojan with Malwarebytes Anti-Malware.
4. Remove .Crinf Ransomware Trojan with STOPZilla AntiMalware
5. Back up your data to secure it against infections and file encryptions by .Crinf Ransomware Trojan in the future

Recovering Your Files

There are several Methods to recover your files. We have arranged them from the most simple ones to the most tech savvy methods.

Method 1: Rename the file extensions.

Many users have reported on forums that they managed to recover a small portion of their files by simply removing the .Crinf extension from them and saving the file in its original one. However this is no guarantee that you will be able to decrypt all your files, only that you may have the chance to decrypt some of them.

Method 2: Use Volume Shadow Copies

There is a solid chance that your volume shadow copies may have not been deleted by the commands executed by this ransomware since they require administrative privileges.
So if you have file history enabled you may have a good chance restoring your data. The safest way to do this may be to boot into safe mode and try external software called, Shadow Explorer. You may download it if you click on this link:
http://www.shadowexplorer.com/downloads.html

Method 3: Use Kaspersky’s utilities or other tools

You may be able to decrypt your data directly in case only a portion of the file in the code itself has been encrypted with weak encryption. Try any of the following published kaspersky tools to decrypt your data:
http://support.kaspersky.com/viruses/utility#
Also here is an RSA decryption tool we managed to find online:
http://www.aeppro.com/download/latest.shtml

Method 4: Use Python in Linux

Here is a suggestion in case the files have a corresponding key that needs to be decoded. It is a more tech savvy option but in case you are determined you may have the chance to decrypt your data:
https://sensorstechforum.com/restore-files-encrypted-via-rsa-encryption-remove-cryptowall-and-other-ransomware-manually/

NOTE! Substantial notification about the .Crinf Ransomware Trojan threat: Manual removal of .Crinf Ransomware Trojan requires interference with system files and registries. Thus, it can cause damage to your PC. Even if your computer skills are not at a professional level, don’t worry. You can do the removal yourself just in 5 minutes, using a malware removal tool.

Vencislav Krustev

A network administrator and malware researcher at SensorsTechForum with passion for discovery of new shifts and innovations in cyber security. Strong believer in basic education of every user towards online safety.

More Posts - Website

Share on Facebook Share
Loading...
Share on Twitter Tweet
Loading...
Share on Google Plus Share
Loading...
Share on Linkedin Share
Loading...
Share on Digg Share
Share on Reddit Share
Loading...
Share on Stumbleupon Share
Loading...
Please wait...

Subscribe to our newsletter

Want to be notified when our article is published? Enter your email address and name below to be the first to know.