|Brief Description:||This Trojan can download and execute more threats onto the infected computer.|
Win32:Downloader-PKU is a heuristic detection for a Trojan that will communicate with a remote hosts and download other malware. This kind of Trojan is used for a variety of purposes. Most common is to download threat such as password-stealing malware. It is also use to deploy other malware also from the same group. Other attackers may utilize this Trojan to download and install rogue software on the computer.
There are instances that antivirus programs may fail to notice Win32:Downloader-PKU. Due to its rootkit function, the Trojan may hide its presence while operating inside the infected computer. With this technique, the threat appends its code to legitimate Windows processes so that only only visible item can be seen running on the computer. The threat may also target Windows driver files as its cradle. Running the device using this driver also executes the code of Win32:Downloader-PKU.
Because Win32:Downloader-PKU is a generic detection, there are no uniform symptoms that user may witness on the PC. Payload of this malware may vary from one version to another. Only visible sign is a frequent alert publish by the installed anti-virus software.
What are the Symptoms of Win32:Downloader-PKU Infection?
Due to the nature of this Trojan, there are no typical symptoms when it infects a computer aside from a constant alert coming from installed anti-virus program. Here is a sample screenshot of how security software averts Win32:Downloader-PKU.
Procedures to Remove Win32:Downloader-PKU
Removal steps on this page will help you get rid of the threat effectively using tools and virus scanners. Please make sure that you will carry out the guide in exact order.
Procedure 1: Scan Computer in Safe Mode Using Installed Anti-virus Program
1. When troubleshooting a PC, one common step is to boot operating system into Safe Mode with Networking. The same approach will be used in the removal of Win32:Downloader-PKU. Please execute instructions based on your Windows OS version.
Start Windows 8 / Windows 10 in Safe Mode with Networking
- Close all running programs on your computer because we will need to restart Windows on this procedure.
- Press and Hold Shift key on your keyboard while clicking on Restart.
- You will then be presented with Troubleshooting Options.
- Click on Troubleshoot icon.
- Then, Click on Advanced Options icon.
- Select Startup Settings icon and then, Click on Restart button.
- When Windows restarts, it will prompt to choose number from the list of options. Press the number on your keyboard that corresponds to Safe Mode with Networking, commonly number 5.
- Once in Safe Mode, please proceed to the next step which is running a virus scan on the computer.
Start in Safe Mode with Networking (Windows XP / Vista / 7 Instruction)
- Please restart the computer and just before Windows start, press F8 on your keyboard repeatedly. You will be presented with Advanced Options Menu.
- From the selections, choose Safe Mode with Networking. Please use keyboard's arrow up/down to navigate between selections and press Enter to proceed.
2. Once your Windows is running in Safe Mode, open your installed anti-virus programs and update it to the most recent version by automatically downloading necessary updates.
3. Thoroughly scan the computer and remove all identified threats. Do not restart or turn off the computer after the scan process. You still need to run another scan. Please follow the next procedure.
Procedure 2: Scan and remove Win32:Downloader-PKU files with MalwareBytes Anti-Malware
To remove Win32:Downloader-PKU, download Malwarebytes Anti-Malware. This tool is effective in getting rid of Trojans, viruses and malware.
1. After downloading, please install the program using the default settings.
2. At the end of the installation, please make sure that it will download necessary updates.
3. Once update has completed, MBAM will launch.
4. Select SCAN from the top menu. Then, click on Threat Scan (Recommended) section.
5. Click on Start Scan to thoroughly scan the computer. Remove all threats detected by this anti-malware program after the process.
Procedure 3: Run extra scan with Junkware Removal Tool
To make sure that no more malicious files linked to Win32:Downloader-PKU are inside the computer, we must run another effective scanner. This time, use Junkware Removal Tool. No installation is necessary with this tool.
1. Click the button above to start the download process. Save the file to your preferred location.
2. Junkware Removal Tool will close all running applications later. So, before executing the file, please Bookmark or Print this page. And then, close all programs.
3. Double-click the JRT.exe file to initiate the tool.
4. It will prompt you to "Press any key to continue."
5. Junkware Removal Tool will create a Restore Point and proceed with the scan. Please wait for the scan process to finish.
6. After scanning the computer, JRT will open a Notepad containing scan logs. It may have not find Win32:Downloader-PKU relevant entities, but it will surely delete any malicious items not found in the previous scans.
Procedure 4: Reset Affected Internet Browser
Reset browser settings of Google Chrome:
1. Open Google Chrome browser.
2. In the address bar, type this: chrome://settings/ and then, press Enter.
3. Navigate at the end of the page and click on Show advanced settings.
4. At the bottom of the page, click on Reset settings to remove all changes made by Win32:Downloader-PKU.
Reset Internet Explorer Settings:
1. Open Internet Explorer software.
2. Navigate to top menu and click Tools > Internet Options.
3. On Internet Options window, select Advanced tab.
4. In order to reverse modifications caused by Win32:Downloader-PKU, click on Reset button to bring back Internet Explorer's settings to their default condition.
Reset Firefox to its default state:
1. Open Mozilla Firefox program.
2. Navigate to top menu and Open Help Menu. Then, select on Troubleshooting Information.
3. Click on Refresh Firefox button to erase the effect of Win32:Downloader-PKU.
Procedure 5: Run Qualys Online Browser Check
Qualys Browser Check performs a security examination on your browser including installed plug-ins and add-ons. At the end of the scan, this tool will recommend on what to remove and give you steps to resolve any vulnerabilities found on the browser.
1. Open Internet browser application that is affected by Win32:Downloader-PKU.
2. Click Here to visit Qualys Browser Check web site.
3. Next, click on "Scan without installing lugin" link.
4. Click on Scan Now button to check and remove Win32:Downloader-PKU and any other malicious add-ons and extensions. You must read and accept "Service User Agreement" to continue.
5. After the scan, you will be presented with Browser Check Summary. Fix any issues and follow the recommendation on the result.
Protect your PC from Win32:Downloader-PKU or Similar Attack
Turn On Safe Browsing Features
Google Chrome's Protection from Dangerous Sites
With Google Chrome's Dangerous Site Protection feature, you will have lesser risks browsing the web. It will display a warning when the site you are trying to visit is suspicious, thus, you can prevent Win32:Downloader-PKU infection. To enable protection from dangerous sites, please do these steps:
1. Open Google Chrome.
2. In the address bar, type this: chrome://settings/ and then, Press Enter.
3. Once on the settings page, click on Show advanced settings... at the bottom of the page to see the rest of the Chrome setup.
4. Locate Privacy section and mark 'Protect you and your device from dangerous sites'.
5. Please restart Google Chrome. New settings keep your browser safe while surfing the web.
Internet Explorer - Activate SmartScreen Filter
Internet Explorer versions 8 and 9 has this feature called SmartScreen Filter. It helps detect phishing web sites and protect you from downloading malicious programs including Win32:Downloader-PKU. To turn on SmartScreen Filter, follow these steps:
1. Please open Internet Explorer.
2. On top menu, select Tools (IE 9). For IE 8, please look for Safety menu.
3. Select SmartScreen Filter from the drop-down list and click on Turn on SmartScreen Filter.
4. Please restart Internet Explorer.
Mozilla Firefox - Block Attack Sites and Web Forgeries
Phishing and Malware Protection is a built-in feature on Firefox version 3 or later. It warns you when a page you are trying to visit contains phishing content or an attack site designed to drop threats such as Win32:Downloader-PKU. To help you keep safe while browsing the Internet using Firefox, please follow this guide:
1. Open Mozilla Firefox browser.
2. On top menu, click on Open Menu. Then select Options from the list.
3. Select Security and put a check mark on the following items:
- Warn me when sites try to install add-ons
- Block reported attack sites
- Block reported web forgeries
Edge Browser - SmartScreen Filter
SmartScreen filter is a built-in feature in Microsoft Edge browser that can help you deter malicious programs such as Win32:Downloader-PKU. It can block malicious web sites and downloads.
1. Open Microsoft Edge browser.
2. Click on More Actions button located at top right corner of the screen.
3. Select Settings from the drop-down list.
4. Under Settings menu, go to Advanced Settings section and click on View Advanced Settings.
5. Scroll down to "help protect my PC from malicious sites and downloads with SmartScreen Filter". Turn it to ON.
6.You may now restart Microsoft Edge browser.