Analysis by: Jeanne Jocson
ALIASES:

Trojan-Ransom.Win32.Cryakl.aom (Kaspersky)

 PLATFORM:

Windows

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

  • 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 is capable of encrypting files in the affected system.

  TECHNICAL DETAILS

File Size: 466,432 bytes
File Type: EXE
Initial Samples Received Date: 23 Dec 2016

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 leaves text files that serve as ransom notes containing the following:

  • to decrypt files write to this mail {contact email}

Dropping Routine

This Trojan drops the following files:

  • {folders and subfolders of the encrypted files}\README.txt←serves as ransom note

Other Details

This Trojan renames encrypted files using the following names:

  • {directory of the encrypted files}\email-{contact email}.ver-CL 1.3.1.0.id-{HID}@@@@@F438-5F1B.randomname-{random name}.{3 random letters}.{random extension}

It is capable of encrypting files in the affected system.