Iiss file extension
.Iiss file extension is a file extension that is associated with the 259th version of STOP (Djvu) ransomware. Security researchers discovered ‘Iiss’ version about a week after the previous one, which is called Efji. Like all other versions of STOP (Djvu) ransomware, Iiss encrypts files and thus makes their contents inaccessible. Criminals demand a ransom in exchange for a decryptor and a unique key, which are necessary for decrypting files.
Fortunately for victims, in some cases .iiss files can be decrypted. This can be done thanks to a free decryptor, which was created by a group of security researchers. This decryptor can decrypt files encrypted with all versions of STOP (Djvu) ransomware, including ‘Iiss’ variant. Read more about the Free Iiss File Decrypt tool or and how to decrypt .iiss files below in this article.
What is Iiss ransomware
Iiss ransomware is really a nasty malware. It infects the system when the user downloads or runs malware infected files. Criminals lure unwary users into downloading ransomware by hiding malicious code within cracked versions of paid software, free software, key generators, and so on. Upon execution, an instance of Iiss virus is installed on victim’s computer.
Once installed on a computer, Iiss encrypts files located on the drives connected to the computer. It uses a strong algorithm and a long key to encrypt files. If, before encrypting the files, the Iiss ransomware was able to establish a connection with its command-and-control (C&C) server, then it uses so called ‘online key’ that is unique to each infected computer. In case when the Iiss virus cannot connect to its command server, it uses the so-called offline key. This key, unlike the online key, is the same for all infected computers and can be determined by security researchers.
In the process of encrypting files, Iiss tries to encrypt all files on the computer, therefore, to speed up the encryption process, it does not encrypt all the contents of the files, but only the first 154kb. At the same time, there are files that the virus does not encrypt: files located in the Windows system directories, files with the extension .bat, ini, .sys, .dll, .lnk and files with the name ‘_readme.txt’. All other files can be encrypted, regardless of where they are located: on the internal disk, external device or cloud storage. Thus, the following common file types can be encrypted:
.ai, .cer, .asset, .nrw, .xlsm, .wpt, .pdf, .mrwref, .sidd, .jpe, .wcf, .wn, .wsc, .ppt, .odc, .dxg, .wma, .zdb, .arw, .kf, .pdd, .wpw, .wpd, .xwp, .wma, .7z, .doc, .svg, .arch00, .apk, .wsh, .z, .zw, .m4a, .sav, .hvpl, .srf, .webdoc, .avi, .indd, .mpqge, .wpe, .ptx, .accdb, .mef, .py, .wgz, .snx, .3dm, .pak, .wp4, .srw, .vdf, .txt, .tax, .bkp, .ztmp, .wbc, .map, .zip, .rgss3a, .zif, .bc7, .x3d, .xbdoc, .x, .jpg, .ods, .css, .bik, .xdb, .dazip, .mdb, .hkx, .kdc, .wpl, .xlsx, .rw2, .wbmp, .lbf, .xpm, .xxx, .mddata, .raw, .cfr, .z3d, .pkpass, .mcmeta, .wdp, .csv, .pptm, .p7c, .dba, .wpd, .mp4, .r3d, .wmd, .slm, .bar, .wpb, .orf, .wbz, .wire, .1, .rtf, .xx, .tor, .xf, .pst, .wmf, .iwd, .ltx, .xbplate, .xld, .rb, .psd, .lvl, .lrf, .xlsb, .wmo, .wri, .y, .ntl, .xls, .fpk, .blob, .xlgc, .dcr, .xmmap, .dwg, .der, .pef, .itm, .bsa, .mdbackup, .wmv, .odt, .dmp, .jpeg, .zi, .ff, .yal, .crw, .zip, .odm, .eps, .x3f, .1st, .3ds, .epk, .sie, .wbd, .hkdb, .wm, .webp, .mov, .layout, .wp6, .ybk, .docx, .ws, .p7b, .ysp, .das, .bay, .w3x, .vtf, .raf, .odp, .wsd, .ncf, .crt, .zabw, .rar, .yml, .d3dbsp, .dng, .menu, .xdl, .wps, .forge, .p12, .wp5, .big, .gho, .bc6, .wotreplay, .0, .t13, .vcf, .kdb, .wp, .wbk, .cr2, .flv, .re4, .gdb, .mdf, .xml, .xy3, .sis, .qdf, .wav, .sid, .vpp_pc, .itl, .pfx, .odb, .zdc, .wmv, .t12, .pptx, .ibank, .fos, .2bp, .wpa, .png, .bkf, .sb, .vpk, .x3f, .xyw, .xls, .mlx, .xll, .dbf, .syncdb, .psk, .xyp, .iwi, .esm, .litemod, .fsh, .wp7, .icxs, .itdb, .3fr, .cdr, .wps, .m2, .xlsx, .pem, .xar, .desc, .wot, .sum, .xlk, .wpg, .wb2, .rwl, .xlsm, .db0, .qic, .xmind, .erf, .upk, .rofl, .sr2, .m3u, .rim, .js, .wdb, .wbm, .vfs0, .sidn, wallet
Each encrypted file receives a new name, the Iiss virus appends the extension ‘.iiss’ at the end of the file name. Thus, if the file was called ‘image.jpg’ before encryption, then after it is encrypted it will be called ‘image.jpg.iiss’. In each folder where the virus encrypted one or more files, it drops a file with the name ‘_readme.txt’.
This file is a ransom demand message. In this message, the authors of the Iiss virus report that the victim’s files were encrypted and if the victim wants to decrypt them, then he needs to purchase a decryptor and a key. Attackers demand to pay them $980, if the victim is ready to pay the ransom within 72 hours, then the size of the ransom is halved to $490. Criminals offer the victim to decrypt one small file for free to confirm the possibility of decrypting .iiss files. Obviously, if the criminals were able to decrypt one file, then this does not guarantee that after receiving the ransom they will give the victim the key and the decryptor.
Text presented in “_readme.txt” file:
Don’t worry, you can return all your files!
All your files like pictures, databases, documents and other important are encrypted with strongest encryption and unique key.
The only method of recovering files is to purchase decrypt tool and unique key for you.
This software will decrypt all your encrypted files.
What guarantees you have?
You can send one of your encrypted file from your PC and we decrypt it for free.
But we can decrypt only 1 file for free. File must not contain valuable information.
You can get and look video overview decrypt tool:
Price of private key and decrypt software is $980.
Discount 50% available if you contact us first 72 hours, that’s price for you is $490.
Please note that you’ll never restore your data without payment.
Check your e-mail “Spam” or “Junk” folder if you don’t get answer more than 6 hours.
To get this software you need write on our e-mail:
Reserve e-mail address to contact us:
Your personal ID:
The message left by the Iiss creators says that files cannot be decrypted without a key and a decryptor. Unfortunately, security researchers confirm that a decryptor and a unique key are required to decrypt files. As we reported above, fortunately there is a free decryptor. Iiss File Decrypt tool can decrypt .iiss files that were encrypted with an offline key. If the files were encrypted with an online key, then they cannot be decrypted, but there are several ways that could help everyone recover the contents of the encrypted files.
|Name||Iiss ransomware, Iiss file virus|
|Type||Ransomware, Filecoder, File locker, Crypto malware, Crypto virus|
|Encrypted files extension||.iiss|
|Ransom amount||$490/$980 in Bitcoins|
|Detection Names||A Variant Of Win32/Kryptik.HHAE, UDS:DangerousObject.Multi.Generic, Ransom:Win32/STOP.BS!MTB, W32.AIDetectVM.malware1, Trojan.Malware.300983.susgen, W32/Kryptik.CGZ.gen!Eldorado, Gen:NN.ZexaF.34590.SqW@aSNMp5UG|
|Symptoms||Photos, documents and music won’t open. You get an error message like ‘Windows can’t open this file’, ‘How do you want to open this file’. Files called like ‘_readme.txt’, ‘READ-ME’, ‘_open me’, _DECRYPT YOUR FILES’ or ‘_Your files have been encrypted” in every folder with an encrypted file. New files on your desktop, with name variants of: ‘HOW_TO_DECRYPT.txt’, ‘DECRYPT.txt’ or ‘README.txt’.|
|Distribution ways||Phishing email scam that attempts to scare users into acting impulsively. Drive-by downloading (when a user unknowingly visits an infected web site and then malware is installed without the user’s knowledge). Social media posts (they can be used to entice users to download malware with a built-in ransomware downloader or click a suspicious link). Flash Drive and other removable media.|
|Removal||Iiss ransomware removal guide|
|Decryption||Iiss File Decrypt Tool|
How to remove Iiss ransomware virus; Recover, Decrypt .iiss files
If your computer is infected with the Iiss virus and the files on it are encrypted, then you need to follow the few steps listed below that will help you find and remove the ransomware, decrypt .iiss files or restore their contents. Before decrypting or recovering files, be sure to check your computer for malicious software. Read carefully the entire instructions below, print it, or open it on your smartphone. This will allow you not to miss anything important.
- How to remove Iiss ransomware
- How to decrypt .iiss files
- How to restore .iiss files
- How to protect your computer from Iiss ransomware
How to remove Iiss ransomware
You need to remove the Iiss ransomware virus and its autostart entries before proceeding to decrypt or restore encrypted files. This must be done since otherwise the ransomware may re-encrypt the restored files. You can stop the ransomware from working, as it is not difficult to do. Another option is to perform a full system scan using free malware removal tools capable of detecting and removing ransomware infection.
It is very important to scan the computer for malware, as security researchers found that spyware could be installed on the infected computer along with the Iiss ransomware. Spyware is a very dangerous security threat as it is designed to steal the user’s personal information such as passwords, logins, contact details, etc. If you have any difficulty removing the Iiss virus, then let us know in the comments, we will try to help you.
To remove Iiss ransomware, follow the steps below:
- Kill the Iiss ransomware process
- Disable the Iiss ransomware Start-Up
- Delete the Iiss ransomware Task
- Delete the Iiss ransomware File
- Scan computer for malware
Kill the Iiss ransomware process
Press CTRL, ALT, DEL keys together.
Click Task Manager. Select the “Processes” tab, look for something suspicious that is the Iiss ransomware then right-click it and select “End Task” or “End Process” option. If your Task Manager does not open or the Windows reports “Task manager has been disabled by your administrator”, then follow the guide: How to Fix Task manager has been disabled by your administrator.
It is not difficult to detect a process related to the Iiss ransomware. When looking for a malicious process, pay attention to the process icon and its name. Most often, this ransomware has a process name in the following format: 4-characters.tmp.exe or 4-characters.exe. For example: 7533.tmp.exe, A4b1.exe, CD15.tmp.exe, 19b2.exe. If you do not find a process with a similar name in the list of processes, then most likely the Iiss ransomware has finished working. But keep in mind, if you do not remove the ransomware autostart entries, as demonstrated below, and do not delete its file, then after a while it may start again, and if it finds unencrypted files, immediately encrypt them.
Disable the Iiss ransomware Start-Up
Select the “Start-Up” tab, look for something similar to the one shown in the example below, right click to it and select Disable.
Close Task Manager.
Delete the Iiss ransomware Task
Type “Task Scheduler” in the search bar. Click Task Scheduler app in the search results. Click “Task Scheduler Library” in the left panel. On the right panel, right-click to “Time Trigger Task” and select Delete.
Close Task Scheduler.
Delete the Iiss ransomware File
Run Task Manager and select the “Start-Up” tab. Right click to the Iiss ransomware Start-Up entry and select Open File Location as shown below.
A directory containing one file will open in front of you, this file is the Iiss ransomware. It needs to be removed. If you try to delete it immediately, then you will not succeed, since this file is protected from deletion.
To delete this file, you need to do the following. Right-click on the file, select Properties. In the window that opens, select Security tab. Next, click the Advanced button below. A window will open as shown in the following example.
Click Disable inheritance. In the Block inheritance dialog box that opens, select the first item (Convert inherited permissions…) as shown below.
In the Permission entries list, select “Deny Everyone”, click Remove button and then OK. Close the file properties window. You should now be able to remove the Iiss ransomware File. Right-click on the file and select Delete.
Scan computer for malware
Zemana AntiMalware (ZAM) is one of the best in its class, it can locate and remove lots of of different security threats, including adware, worms, spyware, ransomware, trojans and malicious software that masqueraded as legitimate system applications. Also Zemana includes another tool called FRST – is a helpful application for manual removal of files and parts of the Windows registry created by crypto malware.
Installing the Zemana is simple. First you’ll need to download Zemana AntiMalware by clicking on the link below. Save it to your Desktop.
Author: Zemana Ltd
Category: Security tools
Update: July 16, 2019
When the download is done, close all apps and windows on your PC system. Open a directory in which you saved it. Double-click on the icon that’s named Zemana.AntiMalware.Setup like below.
When the installation starts, you will see the “Setup wizard” which will help you install Zemana on your PC.
Once installation is complete, you will see window as shown on the screen below.
Now click the “Scan” button to start scanning your computer for the Iiss crypto malware and other security threats. A system scan can take anywhere from 5 to 30 minutes, depending on your personal computer. When a malicious software, adware or potentially unwanted programs are found, the number of the security threats will change accordingly. Wait until the the checking is done.
When Zemana Anti-Malware has completed scanning your computer, Zemana Free will create a list of unwanted applications and ransomware. Make sure all items have ‘checkmark’ and click “Next” button.
The Zemana Anti-Malware will remove Iiss ransomware, other kinds of potential threats like malware and trojans and move the selected threats to the program’s quarantine.
In order to be 100% sure that the computer no longer has the Iiss ransomware virus, we recommend using the Kaspersky virus removal tool (KVRT). Kaspersky virus removal tool is free and easy to use. It can detect and remove ransomware, spyware, potentially unwanted apps, worms, trojans, adware and other malware. KVRT is powerful enough to find and remove malicious registry entries and files that are hidden on the PC.
Download Kaspersky virus removal tool (KVRT) by clicking on the link below.
Author: Kaspersky® lab
Category: Security tools
Update: March 5, 2018
After downloading is finished, double-click on the KVRT icon. Once initialization process is done, you’ll see the Kaspersky virus removal tool screen as shown below.
Click Change Parameters and set a check near all your drives. Click OK to close the Parameters window. Next click Start scan button . KVRT program will scan through the whole PC system for the Iiss ransomware and other trojans and harmful apps. A system scan can take anywhere from 5 to 30 minutes, depending on your personal computer. During the scan Kaspersky virus removal tool will scan for threats present on your computer.
When the scan get finished, Kaspersky virus removal tool will display you the results as displayed in the figure below.
Make sure all items have ‘checkmark’ and press on Continue to start a cleaning task.
How to decrypt .iiss files
Files with the .iiss extension are encrypted and to decrypt them you must use a decryptor and a unique key. You cannot unlock these files simply by deleting the new extension or changing their file name. Fortunately, there is a free Iiss File Decrypt tool that can decrypt .iiss files.
To decrypt .iiss files, use “Iiss File Decrypt tool”
- Download Free Iiss File Decrypt tool from the following link.
STOP Djvu decryptor
- Scroll down to ‘New Djvu ransomware’ section.
- Click the download link and save the decrypt_STOPDjvu.exe file to your desktop.
- Run decrypt_STOPDjvu.exe, read the license terms and instructions.
- On the ‘Decryptor’ tab, using the ‘Add a folder’ button, add the directory or disk where the encrypted files are located.
- Click the ‘Decrypt’ button.
Iiss File Decrypt Tool is a free software that can decrypt the encrypted files only in some cases, when the files were encrypted with an ‘offline key’. If the files were encrypted with an ‘online key’, then they cannot be decrypted. The reason for this is that the decryption key is in the hands of criminals and this key can not be determined. This does not mean that if your files are encrypted with an online key, then their contents are lost forever. Fortunately, there are several ways to recover encrypted files. These methods do not involve the use of decryption and therefore can be used in any case, no matter what key the ransomware used to encrypt files.
How to find out which key was used to encrypt files
Since Iiss File Decrypt Tool only decrypts files encrypted with an offline key, each Iiss’s victim needs to find out which key was used to encrypt the files. Determining the type of key used is not difficult. Below we give two ways. Use any of them.
Find out the type of key using ‘_readme.txt’ file
- Open the ransom demand message (‘_readme.txt’ file).
- Scroll down to the end of the file.
- There you will see a line with the text ‘Your personal ID’.
- Below is a line of characters that starts with ‘0259’ – this is your personal id.
Find out the type of key using ‘PersonalID.txt’ file
- Open disk C.
- Open directory ‘SystemID’.
- Open file named ‘PersonalID.txt’. This file lists ‘Personal ID’s that match the keys that the virus used to encrypt files.
The ‘Personal ID’ is not a key, it is an identifier related to a key that was used to encrypt files. If the ID ends with ‘t1’, then the files are encrypted with an offline key. If the ID does not end with ‘t1’, Iiss virus used an online key. If you could not figure out how to determine which key was used to encrypt files, then we can help. Just write a request here or in the comments below.
Iiss File Decrypt Tool : “No key for New Variant online ID”
If, when you try to decrypt .iiss files, Iiss File Decrypt Tool reports:
No key for New Variant online ID: *
Notice: this ID appears to be an online ID, decryption is impossible
It means that your files are encrypted with an ‘online key’ and their decryption is impossible, since only the Iiss authors have the key necessary for decryption. In this case, you need to use alternative methods listed below to restore the contents of encrypted files.
Iiss File Decrypt Tool : “No key for New Variant offline ID”
If, during decryption of .iiss files, Iiss File Decrypt Tool reports:
No key for New Variant offline ID: *t1
Notice: this ID appears be an offline ID, decryption MAY be possible in the future.
It means the following: your files are encrypted with an ‘offline key’, but the key itself has not yet been obtained by security researchers, in this case, you need to be patient and wait a while, in addition, you can also use alternative ways for recovering encrypted data.
If for some reason you were unable to decrypt the encrypted files, then We recommend to follow the news on our Facebook or YouTube channels. So you ‘ll know right away that it ‘s possible to decrypt .iiss files.
This video step-by-step guide will demonstrate How to use STOP Djvu decryptor to decrypt encrypted files.
How to restore .iiss files
Fortunately, there are several simple ways that give everyone a chance to recover the contents of encrypted files. The methods presented below can help in cases when a free decryptor cannot decrypt .iiss files or when files are encrypted with an online key. Alternative methods of file recovery do not use decryption, so there is no need for a key and decryptor. Before you begin, you must be 100% sure that the computer does not have active ransomware. Therefore, if you have not yet checked your computer for ransomware, do it now, use free malware removal tools or return to step 1 above.
Recover .iiss files with ShadowExplorer
Now proceed to recover .iiss files. We hope you have already completed all the steps that we discussed above. First of all, try to recover encrypted files using a free tool called ShadowExplorer. This program will allow you to recover your files from Shadow Volume Copies. These copies are created automatically by the Windows OS when you work with your files.
Unfortunately, Iiss virus can automatically delete these copies and thus prevent you from recovering your files. Nevertheless, in some cases, the ransomware cannot delete all copies, and the user gets the opportunity to quickly restore all files. Therefore, you should definitely try this method!
ShadowExplorer can be downloaded from the following link. Save it on your Microsoft Windows desktop.
Category: Security tools
Update: September 15, 2019
Once the downloading process is done, extract the downloaded file to a directory on your personal computer. This will create the necessary files as on the image below.
Launch the ShadowExplorerPortable program. Now choose the date (2) that you wish to restore from and the drive (1) you want to restore files (folders) from similar to the one below.
On right panel navigate to the file (folder) you want to recover. Right-click to the file or folder and press the Export button like below.
And finally, specify a folder (your Desktop) to save the shadow copy of encrypted file and press ‘OK’ button.
This video step-by-step guide will demonstrate How to recover encrypted files using Shadow Explorer.
Recover .iiss files using PhotoRec to
Another really working way to recover .iiss files is to use a free tool named PhotoRec. It is created to recover deleted or lost files. Does the Iiss ransomware block this method? Fortunately, the ransomware cannot block this method of recovering the contents of encrypted files. The more you used (moved, deleted, modified) files before infection, the greater the chance that you will be able to recover them.
Download PhotoRec on your Windows Desktop from the link below.
Category: Security tools
Update: March 1, 2018
Once downloading is complete, open a directory in which you saved it. Right click to testdisk-7.0.win and select Extract all. Follow the prompts. Next please open the testdisk-7.0 folder as displayed below.
Double click on qphotorec_win to run PhotoRec for MS Windows. It will show a screen as displayed in the following example.
Choose a drive to recover as displayed in the following example.
You will see a list of available partitions. Choose a partition that holds encrypted personal files as displayed on the image below.
Click File Formats button and specify file types to restore. You can to enable or disable the recovery of certain file types. When this is complete, press OK button.
Next, click Browse button to choose where recovered personal files should be written, then click Search. We strongly recommend that you save the recovered files to an external drive.
Count of recovered files is updated in real time. All restored personal files are written in a folder that you have chosen on the previous step. You can to access the files even if the recovery process is not finished.
When the recovery is done, click on Quit button. Next, open the directory where recovered documents, photos and music are stored. You will see a contents similar to the one below.
All restored documents, photos and music are written in recup_dir.1, recup_dir.2 … sub-directories. If you’re looking for a specific file, then you can to sort your restored files by extension and/or date/time.
This video step-by-step guide will demonstrate How to recover encrypted files using PhotoRec.
How to protect your computer from Iiss ransomware
Most antivirus programs already have built-in protection system against the ransomware virus. Therefore, if your personal computer does not have an antivirus program, make sure you install it. As an extra protection, run the HitmanPro.Alert. All-in-all, HitmanPro.Alert is a fantastic utility to protect your personal computer from any ransomware. If ransomware is detected, then HitmanPro.Alert automatically neutralizes malware and restores the encrypted files. HitmanPro.Alert is compatible with all versions of Windows operating system from MS Windows XP to Windows 10.
Please go to the link below to download HitmanPro Alert. Save it on your Windows desktop or in any other place.
Category: Security tools
Update: March 6, 2019
When downloading is finished, open the file location. You will see an icon like below.
Double click the HitmanPro Alert desktop icon. When the utility is opened, you will be displayed a window where you can select a level of protection, similar to the one below.
Now click the Install button to activate the protection.
To sum up
This guide was created to help all victims of the Iiss ransomware virus. We tried to give answers to the following questions: how to remove ransomware; how to decrypt .iiss files; how to recover encrypted files, if Iiss File Decrypt tool does not help; what is an online key and what is an offline key. We hope that the information presented in this manual has helped you.
If you have questions, then write to us, leaving a comment below. If you need more help with Iiss related issues, go to here.