Abyss Locker Ransomware Threat Overview

Report Summary:
This report provides a detailed analysis of Abyss Locker, a relatively new threat group that emerged in 2023 and has since caused multiple incidents. Also known as Abyss ransomware, this group specializes in swift and decisive intrusions designed to cripple victims with ransomware.

Threat Actor Group:
The actor group behind Abyss Locker is not clearly identified due to their relatively new emergence. However, they exhibit high levels of sophistication and determination.

Report Reliability: A – Completely reliable

Abyss Locker Attack Analysis:

Initial Access:
Abyss Locker operators primarily gain initial access through exploiting known vulnerabilities in out-of-date software or using stolen credentials obtained from the dark web. They also employ phishing campaigns to trick users into executing malware.

Privilege Escalation & Defense Evasion:
Once inside, the group uses various techniques such as token impersonation and living-off-the-land tools to escalate privileges and evade detection. They often disable security software and modify system files to maintain persistence.

Lateral Movement:
Abyss Locker operators move laterally within the network using legitimate tools like PsExec and remote desktop protocols (RDP). They also employ pass-the-hash techniques to bypass credentials.

*Command & Control:**
The group uses custom-built C&C infrastructure, often communicating over SSL/HTTPS to evade detection. They employ various anti-VM/AV techniques to prevent analysis of their malware.

Data Exfiltration:
Before encrypting files, Abyss Locker operators exfiltrate data from the network using tools like WinRAR and FTP clients. This data is used as leverage in ransom negotiations.

Encryption & Ransomware Deployment:
Abyss Locker encrypts files using strong encryption algorithms and appends its extension (e.g., ‘.abyss’). It targets a wide range of file types, including documents, images, and executables. After encryption, a ransom note is generated with instructions on how to contact the operators.

Recommendations:

• Patch management: Regularly update and patch systems to protect against known vulnerabilities.
• Strong password policy: Enforce complex passwords and consider using password managers or multi-factor authentication (MFA).
• Phishing awareness: Train users to recognize and report phishing attempts.
• Network segmentation: Segment networks to limit lateral movement in case of a breach.
• Regular backups: Implement regular data backups to minimize data loss in case of ransomware infection.
• Anti-malware software: Use up-to-date anti-malware software with behavioral analysis capabilities.

  External References:
  AlienVault OTX
  Sygnia Blog: Abyss Locker Ransomware Attack Analysis