jeff_dev_ransomware

YARA-2025-0570 Critical general Active

Rule to detect Jeff DEV Ransomware

jeff_dev_ransomware.yar Valid Syntax
rule jeff_dev_ransomware {

   meta:
   
      description = "Rule to detect Jeff DEV Ransomware"
      author = "Marc Rivero | @seifreed"
      reference = "https://www.bleepingcomputer.com/news/security/the-week-in-ransomware-august-31st-2018-devs-on-vacation/"
      
   strings:

      $s1 = "C:\\Users\\Umut\\Desktop\\takemeon" fullword wide
      $s2 = "C:\\Users\\Umut\\Desktop\\" fullword ascii
      $s3 = "PRESS HERE TO STOP THIS CREEPY SOUND AND VIEW WHAT HAPPENED TO YOUR COMPUTER" fullword wide
      $s4 = "WHAT YOU DO TO MY COMPUTER??!??!!!" fullword wide

   condition:

      ( uint16(0) == 0x5a4d and filesize < 5000KB ) and all of them
}

Rule Metadata

description
Rule to detect Jeff DEV Ransomware
author
Marc Rivero | @seifreed
reference
https://www.bleepingcomputer.com/news/security/the-week-in-ransomware-august-31st-2018-devs-on-vacation/

String Definitions

{"name":"$s1","value":"\"C:\\\\Users\\\\Umut\\\\Desktop\\\\takemeon\" fullword wide"}
{"name":"$s2","value":"\"C:\\\\Users\\\\Umut\\\\Desktop\\\\\" fullword ascii"}
{"name":"$s3","value":"\"PRESS HERE TO STOP THIS CREEPY SOUND AND VIEW WHAT HAPPENED TO YOUR COMPUTER\" fullword wide"}
{"name":"$s4","value":"\"WHAT YOU DO TO MY COMPUTER??!??!!!\" fullword wide"}

Threat Analysis

This YARA rule is designed to detect general threats.

Severity Level: Critical

The rule uses pattern matching to identify specific byte sequences, strings, or behavioral patterns associated with malicious activity.

Detection Capabilities

  • File-based detection for executables and documents
  • Memory scanning for running processes
  • Network traffic analysis support

Command Line Usage

# Scan a single file
yara jeff_dev_ransomware.yar /path/to/suspicious/file

# Scan a directory recursively
yara -r jeff_dev_ransomware.yar /path/to/directory/

# Scan with metadata output
yara -m jeff_dev_ransomware.yar target_file

# Scan process memory (Linux)
yara jeff_dev_ransomware.yar /proc/[pid]/exe

Integration Examples

Python (yara-python)

import yara
rules = yara.compile(filepath='jeff_dev_ransomware.yar')
matches = rules.match('/path/to/file')

ClamAV Integration

clamscan --yara-rules=jeff_dev_ransomware.yar /path/to/scan

Rule Information

YARA ID
YARA-2025-0570
Created
August 19, 2025
Last Updated
August 19, 2025
Last Imported
Never

Threat Intelligence

Risk Level Critical
Category general
Detection Confidence Analysis Pending
False Positive Rate Not Available
Last Seen in Wild No Data

Export Options