TROJ_CRILOCK.YMO
Trojan:Win32/Crilock (Microsoft); Trojan-Ransom.Win32.Blocker.enwh(Kasperksy); Trojan.Cryptolocker(Norton); Trojan.Win32.Crilock(Ikarus)
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 deletes itself after execution.
TECHNICAL DETAILS
815,104 bytes
EXE
Yes
19 May 2014
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:
- %AppDataLocal%\{random filename}.exe
(Note: %AppDataLocal% is the Local Application Data folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local on Windows Vista and 7.)
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 = "%AppDataLocal%\{random filename}.exe"
HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\RunOnce
*CryptoLocker = "%AppDataLocal%\{random filename}.exe"
Other System Modifications
This Trojan adds the following registry entries:
HKEY_CURRENT_USER\Software\CryptoLocker_0388
VersionInfo = "{hex values}"
HKEY_CURRENT_USER\Software\CryptoLocker_0388
PublicKey = "{hex values}"
HKEY_CURRENT_USER\Software\CryptoLocker_0388
Wallpaper = "{hex values}"
HKEY_CURRENT_USER\Software\CryptoLocker_0388\
Files
{path and filename of encrypted files} = "{hex values}"
HKEY_CLASSES_ROOT\{random characters}\shell\
open\command
(Default) = ""%AppDataLocal%\{random filename.exe}" - "%1" %*"
HKEY_CURRENT_USER\Software\Classes\
{random characters}\shell\open\
command
(Default) = ""%AppDataLocal%\{random filename.exe}" - "%1" %*"
Dropping Routine
This Trojan drops the following files:
- %Desktop%\{random filename}.bmp
(Note: %Desktop% is the current user's desktop, which is usually C:\Documents and Settings\{User Name}\Desktop on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\Desktop on Windows Vista and 7.)
Other Details
This Trojan connects to the following possibly malicious URL:
- {random character}.ru
- {random character}.info
- {random character}.co.uk
- {random character}.biz
- {random character}.org
- {random character}.com
- {random character}.net
It deletes itself after execution.