Ransom_AMNESIA.G
DeepScan:Generic.Ransom.Amnesia.F42DEF8A (Bitdefender), Trj/RansomCrypt.D (Panda)
Windows
Threat Type: Ransomware
Destructiveness: No
Encrypted:
In the wild: Yes
OVERVIEW
This Ransomware arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.
It is capable of encrypting files in the affected system.
TECHNICAL DETAILS
67072 bytes
EXE
02 Nov 2017
Arrival Details
This Ransomware 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 Ransomware drops the following files:
- %User Temp%\{GUID}.bat
(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)
It drops the following copies of itself into the affected system:
- %Application Data%\Ghrome.exe
(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)
It adds the following processes:
- %System%\cmd.exe /c vssadmin Delete Shadows /for=C: /All
- %System%\cmd.exe /c vssadmin Delete Shadows /for=D: /All
- %System%\cmd.exe /c vssadmin Delete Shadows /for=E: /All
- %System%\cmd.exe /c vssadmin Delete Shadows /for=F: /All
- %System%\cmd.exe /c wbadmin DELETE SYSTEMSTATEBACKUP -keepVersions:0
- %System%\cmd.exe /c wmic SHADOWCOPY DELETE
- %System%\cmd.exe /c vssadmin Delete Shadows /All /Quiet
- %System%\cmd.exe /c bcdedit /set {default} recoveryenabled No
- %System%\cmd.exe /c bcdedit /set {default} bootstatuspolicy ignoreallfailures
(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)
It leaves text files that serve as ransom notes containing the following:
- {encrypted file path}\HOW TO RECOVER ENCRYPTED FILES.TXT
Autostart Technique
This Ransomware adds the following registry entries to enable its automatic execution at every system startup:
HKCU\Software\Microsoft\
Windows\CurrentVersion\RunOnce
{B5135AD2-D7D9-FFDC-0A8E-143026FB1938} = %Application Data%\Ghrome.exe
Other System Modifications
This Ransomware adds the following registry keys:
HKCU\Software\{B5135AD2-D7D9-FFDC-0A8E-143026FB1938}
It modifies the Internet Explorer Privacy Settings.
Other Details
This Ransomware is capable of encrypting files in the affected system.