Jump to content

Removal instructions for MyDefender

Recommended Posts

  • Staff

What is MyDefender?

The Malwarebytes research team has determined that MyDefender is a fake anti-malware application. These so-called "rogues" use intentional false positives to convince users that their systems have been compromised. Then they try to sell you their software, claiming it will remove these threats. In extreme cases the false threats are actually the very trojans that advertise or even directly install the rogue. You are strongly advised to follow our removal instructions below.

How do I know if I am infected with MyDefender?

This is how the main screen of the rogue application looks:


You will find this icon in your taskbar:


And see these warnings:



How did MyDefender get on my computer?

Rogue programs use different methods for spreading themselves. This particular one was downloaded from their site.

How do I remove MyDefender?

Our program Malwarebytes Anti-Malware can detect and remove this rogue application.

  • Please download Malwarebytes Anti-Malware to your desktop.
  • Double-click mbam-setup.exe and follow the prompts to install the program.
  • At the end, be sure a check-mark is placed next to the following:
    • Update Malwarebytes Anti-Malware
    • Launch Malwarebytes Anti-Malware

    [*]Then click Finish.

    [*]If an update is found, it will download and install the latest version.

    [*]Once the program has loaded, select Perform quick scan, then click Scan.

    [*]When the scan is complete, click OK, then Show Results to view the results.

    [*]Be sure that everything is checked, and click Remove Selected. Reboot your computer if prompted.

    [*]When completed, a log will open in Notepad. The rogue application should now be gone.

Is there anything else I need to do to get rid of MyDefender?

  • No, Malwarebytes Anti-Malware removes MyDefender completely.

How would the full version of Malwarebytes Anti-Malware help protect me?

We hope our application has helped you eradicate this malicious software. If your current security solution let this infection through, you might please consider purchasing the FULL version of Malwarebytes Anti-Malware for additional protection.

As you can see below the full version of Malwarebytes Anti-Malware would have protected you against the MyDefender rogue. It would have warned you before the rogue could install itself, giving you a chance to stop it before it became too late.


Technical details for experts

Signs in a HijackThis log:

C:\Program Files\mydefender\mydefender.exe
C:\Program Files\mydefender\mydefen.exe

O4 - HKLM\..\Run: [mydefens] C:\Program Files\mydefender\mydefens.exe

Alterations made by the installer:

File System
Adds the folder C:\Documents and Settings\{username}\Start Menu\Programs\mydefender
Adds the file Uninstall.lnk"="09:53 28/04/12 643 bytes
Adds the file mydefender.lnk"="09:53 28/04/12 706 bytes
Adds the file mydefender Ȩ������.url"="09:53 28/04/12 54 bytes
Adds the folder C:\Program Files\mydefender
Adds the file mydefens.exe"="09:53 28/04/12 10240 bytes
Adds the file mydefender.exe"="09:53 28/04/12 798720 bytes
Adds the file mydefender.dat"="09:53 28/04/12 69632 bytes
Adds the file mydefen.exe"="09:53 28/04/12 14848 bytes
In the existing folder C:\WINDOWS\system32
Adds the file uninstmdf.exe"="09:53 28/04/12 9216 bytes

"mydefens"="'C:\Program Files\mydefender\mydefens.exe'"

Malwarebytes Anti-Malware log:

Malwarebytes Anti-Malware

Database version: v2012.04.28.01

Windows XP Service Pack 3 x86 NTFS
Internet Explorer 8.0.6001.18702
{username} :: MBAM-D3E8C91ACC [administrator]

4/28/2012 9:57:40 AM
mbam-log-2012-04-28 (09-57-40).txt

Scan type: Quick scan
Scan options enabled: Memory | Startup | Registry | File System | Heuristics/Extra | Heuristics/Shuriken | PUP | PUM
Scan options disabled: P2P
Objects scanned: 169356
Time elapsed: 51 second(s)

Memory Processes Detected: 2
C:\Program Files\mydefender\mydefender.exe (Rogue.MyDefender) -> 1000 -> Delete on reboot.
C:\Program Files\mydefender\mydefen.exe (Rogue.MyDefender) -> 716 -> Delete on reboot.

Memory Modules Detected: 1
C:\Program Files\mydefender\mydefender.dat (Rogue.MyDefender) -> Delete on reboot.

Registry Keys Detected: 1
HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\mydefender (Rogue.MyDefender) -> Quarantined and deleted successfully.

Registry Values Detected: 2
HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run|mydefens (Rogue.MyDefender) -> Data: C:\Program Files\mydefender\mydefens.exe -> Quarantined and deleted successfully.
HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\mydefender|HelpLink (Rogue.MyDefender) -> Data: http://www.mydefender.co.kr -> Quarantined and deleted successfully.

Registry Data Items Detected: 0
(No malicious items detected)

Folders Detected: 1
C:\Program Files\mydefender (Rogue.MyDefender) -> Delete on reboot.

Files Detected: 6
C:\Program Files\mydefender\mydefender.exe (Rogue.MyDefender) -> Delete on reboot.
C:\Program Files\mydefender\mydefen.exe (Rogue.MyDefender) -> Delete on reboot.
C:\Program Files\mydefender\mydefens.exe (Rogue.MyDefender) -> Quarantined and deleted successfully.
C:\Documents and Settings\{username}\Desktop\mdfs_game.exe (Rogue.MyDefender) -> Quarantined and deleted successfully.
C:\WINDOWS\system32\uninstmdf.exe (Rogue.MyDefender) -> Quarantined and deleted successfully.
C:\Program Files\mydefender\mydefender.dat (Rogue.MyDefender) -> Delete on reboot.


As mentioned before the full version of Malwarebytes Anti-Malware could have protected your computer against this threat.

We use different ways of protecting your computer(s):

  • Dynamically Blocks Malware Sites & Servers
  • Malware Execution Prevention

Save yourself the hassle and get protected.

Link to post
Share on other sites

  • Recently Browsing   0 members

    • No registered users viewing this page.
Back to top
  • Create New...

Important Information

This site uses cookies - We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.