ALIASES:

Ransom:Win32/Cerber!rfn (Microsoft); Ransom-FCJ!B1BFA47E9776 (McAfee); Ransom.Cry (Symantec); Trojan-Ransom.Win32.SageCrypt.c (Kaspersky); Troj/Cerber-ADI (Sophos); Trojan.Win32.Generic!BT (Sunbelt); Trojan horse Atros4.CCCV (AVG)

 PLATFORM:

Windows

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:

  • 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

File Size: 352,328 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 01 Mar 2017

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.

Other System Modifications

This Trojan adds the following registry keys:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\
Control\StillImage\Debug\
wiadss.DLL

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Control\StillImage\Debug\
wiadss.DLL
DebugFlags = "1"

Dropping Routine

This Trojan drops the following files:

  • %User Profile%\Application Data\OYcpeznp.tmp
  • %User Profile%\Application Data\GICD35lK.exe
  • %User Startup%\dnxnxx6U.lnk

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.. %User Startup% is the current user's Startup folder, which is usually C:\Documents and Settings\{user}\Start Menu\Programs\Startup on Windows 2000 and XP, and C:\Documents and Settings\{User name}\Start Menu\Programs\Startup on Windows Vista, 7, and 8.)

Other Details

This Trojan connects to the following possibly malicious URL:

  • {BLOCKED}.116.41

It deletes itself after execution.

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine: 9.8

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.

Step 2

Delete this registry key

[ Learn More ]

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_LOCAL_MACHINE\System\CurrentControlSet\Control\StillImage\Debug
    • wiadss.DLL

Step 3

Delete this registry value

[ Learn More ]

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_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\StillImage\Debug\wiadss.DLL
    • DebugFlags = "1"

Step 4

Search and delete these components

[ Learn More ]
There may be some components that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.
  • %User Profile%\Application Data\OYcpeznp.tmp
  • %User Profile%\Application Data\GICD35lK.exe
  • %User Startup%\dnxnxx6U.lnk

Step 5

Scan your computer with your Trend Micro product to delete files detected as Ransom_SAGE.KP. 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.


Did this description help? Tell us how we did.