TROJ_CRILOCK.AG
W32/Blocker.CLLO!tr (Fortinet), Win32/Filecoder.BQ trojan (ESET)
Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)
Threat Type: Trojan
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It executes then deletes itself afterward.
It modifies the Internet Explorer Zone Settings.
TECHNICAL DETAILS
743,424 bytes
EXE
04 Oct 2013
Arrival Details
This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
Installation
This Trojan drops the following copies of itself into the affected system and executes them:
- %Application Data%\{random file name}.exe
(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)
It executes then deletes itself afterward.
Autostart Technique
This Trojan adds the following registry entries to enable its automatic execution at every system startup:
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
CryptoLocker = "%Application Data%\{random file name}.exe"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\RunOnce
*CryptoLocker = "%Application Data%\{random file name}.exe"
Web Browser Home Page and Search Page Modification
This Trojan modifies the Internet Explorer Zone Settings.
Other Details
This Trojan connects to the following possibly malicious URL:
- {pseudorandom domain}.biz/home
- {pseudorandom domain}.ru/home
- {pseudorandom domain}.net/home
- {pseudorandom domain}.info/home
- {pseudorandom domain}.co.uk/home
- {pseudorandom domain}.com/home
- {pseudorandom domain}.org/home