Analysis by: Nikko Tamana
ALIASES:

Trojan-Ransom.Win32.Nubi.f (Kaspersky), Ransom:Win32/Anunau.A (Microsoft)

 PLATFORM:

Windows

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

  • 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

File Size: 55808 bytes
File Type: EXE
Initial Samples Received Date: 13 Oct 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.

Autostart Technique

This Ransomware adds the following registry entries to enable its automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
Adobe Acrobat Optimizer x86 = {malware file path and file name}.exe -autorun

Other Details

This Ransomware connects to the following possibly malicious URL:

  • stati{BLOCKED}.dns.army/rec.php?msg=

It is capable of encrypting files in the affected system.

Ransomware Routine

This Ransomware appends the following extension to the file name of the encrypted files:

  • .[anubi@cock.li].anubi

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

  • {encrypted file path}\__READ_ME__.txt