Rewterz Threat Alert – STOP/DJVU Ransomware – Active IOCs

Severity

High

Analysis Summary

The STOP/DJVU ransomware initially made headlines in 2018 and has since been attacking individuals all around the world. It’s widespread on torrent sites and other platforms in software crack packages and adware bundles. The STOP/DJVU ransomware is a Trojan that encrypts files. It infiltrates your computer invisibly and encrypts all of your data, making them unavailable to you. It leaves a ransom letter warning which demands money in exchange for decrypting your data and making them available to you again. Malware is delivered via cracked applications, fake set-up apps keygens, activators, and Windows updates. It does not utilize local information like keyboard layouts or timezone settings to prevent infecting victims in certain countries; instead, it uses the information returned by a request to https[:]//api.2ip.ua/geo.json. The card’s MAC address is utilized to provide unique identification for the system. This identity is provided to STOP’s command and control server, which responded with an RSA-2048 public key for encryption. Additional malware, including an information stealer known as Vidar, is then downloaded and installed.

Impact

• Information Theft
• File Encryption

Indicators of Compromise

MD5

• 9d1bf8a7eba8e6a3b8df05a8c53fe4e5

SHA-256

• 1472de28dffe2b040e5e396e31ca7d63633cef487ce8f0fd9dff13ee98d5d3e9

SHA-1

• 0833c7bcbff9e9e74c898c21c1b5121bf6d45a8c

Remediation

• Block all threat indicators at your respective controls.
• Search for Indicator of compromise (IOCs) in your environment utilizing your respective security controls
• Maintain cyber hygiene by updating your anti-virus software and implementing a patch management lifecycle.
• Maintain Offline Backups – In a ransomware attack, the adversary will often delete or encrypt backups if they have
• access to them. That’s why it’s important to keep offline (preferably off-site), encrypted backups of data and test them
• regularly.
• Emails from unknown senders should always be treated with caution.
• Never trust or open ” links and attachments received from unknown sources/senders.