TROJ_MEDFOS.FVL
W32/Medfos.AD!tr (Fortinet); Medfos.e (McAfee)
Windows 2000, Windows XP, Windows Server 2003
![](/vinfo/imgFiles/legend.jpg)
Threat Type: Trojan
Destructiveness: No
Encrypted: Yes
In the wild: Yes
OVERVIEW
Dropped by other malware
This Trojan modifies a certain file where it inserts a line line under the [ExtensionDirs] section.
This Trojan may be dropped by other malware.
As of this writing, the said sites are inaccessible.
TECHNICAL DETAILS
Varies
DLL
Yes
21 Jun 2012
Downloads files, Connects to URLs/IPs
Arrival Details
This Trojan may be dropped by other malware.
Installation
This Trojan adds the following processes:
- default browser process
It creates the following folders:
- %Application Data%\{AF8106AD-BA42-11E1-8270-B8AC6F996F26}
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.)
Other System Modifications
This Trojan adds the following registry entries as part of its installation routine:
HKEY_CURRENT_USER\Software\Mozilla\
Firefox\Extensions
{AF8106AD-BA42-11E1-8270-B8AC6F996F26} = %Application Data%\{AF8106AD-BA42-11E1-8270-B8AC6F996F26}
Download Routine
This Trojan accesses the following websites to download files:
- http://{BLOCKED}oadfile.com/file/id=AwAyAAEAyq8QAAEFAJAAAAAAAAAAIwwGEAsAAACtBoGv4RFCuqy4cIImb5lvVVVVVVVVVVVVVVVVVVVVVQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAADRW&c=3
- http://{BLOCKED}load.com/file/id=BAAyAAEAvTwQAAEFBgAAAAAAAAAAAAAAAAAAAAAjDAYQCwAAAO shSLhEUC6rLhwgiZvmW8AAFVVVVVVVVVVVVVVVVVVVVVPTs0BuoP8V5PYPABURUtFV19WTn9XR08uTEtGMjYyAhORIicbl80HAAAAAAA0VgAA&rt=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
As of this writing, the said sites are inaccessible.
NOTES:
This Trojan modifies the file %User Profile%\Mozilla\Firefox\Profiles\4wwmjcqo.default\extensions.ini where it inserts the following line under the [ExtensionDirs] section:
- %Application Data%\{AF8106AD-BA42-11E1-8270-B8AC6F996F26}
SOLUTION
9.200
9.210.03
22 Jun 2012
Step 1
For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.
Step 2
Restart in Safe Mode
Step 3
Search and delete these folders
- %Application Data%\{AF8106AD-BA42-11E1-8270-B8AC6F996F26}
Step 4
Delete this registry value
Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.
- In HKEY_CURRENT_USER\Software\Mozilla\Firefox\Extensions
- {AF8106AD-BA42-11E1-8270-B8AC6F996F26} = %Application Data%\{AF8106AD-BA42-11E1-8270-B8AC6F996F26}
- {AF8106AD-BA42-11E1-8270-B8AC6F996F26} = %Application Data%\{AF8106AD-BA42-11E1-8270-B8AC6F996F26}
Step 5
Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_MEDFOS.FVL. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.
Step 6
Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.
- %User Profile%\Mozilla\Firefox\Profiles\4wwmjcqo.default\extensions.ini
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