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
- c4967a7c3dbbd5ef935c0107222c8595
SHA-256
- 8e6ac7d17a31abf450dda741a65bef6ab53462954607b458c91bd3006740923d
SHA-1
- c680d5bb7eef9d21d63f77728f8e164d486b6cb0
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.