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Added to the Dr.Web virus database: 2015-10-13

Virus description added:


  • e4627cb007e850951d517a9df6e2d85fd47bf380 (crx)
  • 6cd9411ba0bf32e652b6c4d0d196354b48d67164 (back.js)
  • 4741b9e5de51828087b04fa466338248eb490d17 (page.js)

Trojan made as a Google Chrome browser extension. It is designed to perform web injections into webpages viewed by users and to block third-party advertisements.

An incident of Trojan distribution using automatically opened tab in a browser window was detected. This tab does not allow to close itself and shows a window offering to install this malicious extension. Trojan is distributed under the name “Щит безопасности KIS” (KIS Security Guard) and consists of two obfuscated files written in JavaScript: back.js and page.js. The plug-in has the following manifest:

    "update_url": "",
    "background": {
        "scripts": ["back.js"]
    "content_scripts": [ {
        "js": ["page.js"],
        "matches": ["*://*/*"],
        "run_at" : "document_start"
    } ],
    "icons": {
        "128": "icons/128.png"
    "name": "Щит безопасности KIS",
    "description": "Защита вашего пк от вредоносных ссылок и программ",
    "manifest_version": 2,
    "content_security_policy": "script-src 'self' 'unsafe-eval'; object-src 'self'",
    "version": "2.5",
    "permissions": [
        "storage", "tabs", "webRequest", "webRequestBlocking", "unlimitedStorage",
        "webNavigation", "<all_urls>", "notifications", "cookies",  "downloads", "history",
        "management", "contextMenus", "contentSettings", "http://*/*", "https://*/*", "topSites"

During installation, the plug-in requires the following privileges:


A core set of Trojan functions:

  • injecting random JavaScript script received from the command and control server into the webpages;
  • blocking showing third-party advertisements at all websites, except those that are listed in the configuration;
  • disabling Chrome extensions upon receiving a command from the server;
  • misusing the user’s account in the “Odnoklassniki” social network;

A list of “trusted advertisers” contains the following domains:

['', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '']

Trojan.BPLug.1041 sends user ID and data about other Chrome extensions installed at the infected computer to the cybercriminal server. During sending data, server may specify the Trojan which extensions should be disabled. Reply from the command and control server may have the following structure:


Separate function is responsible for showing advertisement. With the help of this function the Trojan analyzes the content of a webpage opened by a user. If its context includes sexual content, Trojan.BPLug.1041 loads advertisement of the corresponding subject from two separate networks. This extension also contains the list of websites where the Trojan does not show advertisement:

['', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '']

If a user makes a log in to the “Odnoklassniki” social network, Trojan.BPLug.1041 tries to provide a certain application with the access to the API of this social network under the user name by means of the authorization by OAuth protocol. During this process, privileges are required to change the status, view, edit, and upload photos; viewing and sending messages under the user name and some others.

There are three more extensions under the name “Щит безопасности KISi” (KIS Security Guard) in Chrome extension online store. All these extensions are created by one and the same author, but the functionality of two others reduces to loading scripts form the command and control server.

  • f347dc275dcc6acee1f658bed64f8ea4908c0ac5 (crx) - extension_id dogojpdglbhldjonllhpghgalomnljgo
  • 50d8466b72d06ae6086489ceefbe295e14f7b8ab (crx) - extension_id hglilpokbpmhgcgmlgkdchepkbdefkaj
  • 95dafb355559fce5249d7cc419ba80565d719e23 (crx) - extension_id mebffcdicpfbajjjgiconipfgomhoido

Curing recommendations

  1. If the operating system (OS) can be loaded (either normally or in safe mode), download Dr.Web Security Space and run a full scan of your computer and removable media you use. More about Dr.Web Security Space.
  2. If you cannot boot the OS, change the BIOS settings to boot your system from a CD or USB drive. Download the image of the emergency system repair disk Dr.Web® LiveDisk , mount it on a USB drive or burn it to a CD/DVD. After booting up with this media, run a full scan and cure all the detected threats.
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Download by serial number

Use Dr.Web Anti-virus for macOS to run a full scan of your Mac.

After booting up, run a full scan of all disk partitions with Dr.Web Anti-virus for Linux.

Download Dr.Web

Download by serial number

  1. If the mobile device is operating normally, download and install Dr.Web for Android. Run a full system scan and follow recommendations to neutralize the detected threats.
  2. If the mobile device has been locked by Android.Locker ransomware (the message on the screen tells you that you have broken some law or demands a set ransom amount; or you will see some other announcement that prevents you from using the handheld normally), do the following:
    • Load your smartphone or tablet in the safe mode (depending on the operating system version and specifications of the particular mobile device involved, this procedure can be performed in various ways; seek clarification from the user guide that was shipped with the device, or contact its manufacturer);
    • Once you have activated safe mode, install the Dr.Web for Android onto the infected handheld and run a full scan of the system; follow the steps recommended for neutralizing the threats that have been detected;
    • Switch off your device and turn it on as normal.

Find out more about Dr.Web for Android