⚠️ Overview

GhostLocker is a ransomware-as-a-service (RaaS) family first identified in June 2022 by researchers at Cyble, operating under a Russian-speaking threat group commonly tracked as Ghost Team. It belongs to the ransomware category and employs double extortion tactics, combining file encryption with data exfiltration to pressure victims into paying ransoms.

🔧 Technical Capabilities

GhostLocker is written in .NET (C#) and uses AES-256 encryption to lock files, appending the .ghost extension to encrypted objects. It propagates via SMB exploitation, RDP brute-force attacks, and phishing emails containing malicious attachments or links. The malware communicates with its command-and-control (C2) infrastructure over HTTPS to a Tor hidden service, ensuring operational security. Persistence is achieved through scheduled tasks and registry Run keys under HKEY_CURRENT_USERSoftwareMicrosoftWindowsCurrentVersionRun. It evades analysis by checking for sandbox environments, such as the presence of common debugging processes (e.g., procmon.exe, wireshark.exe), and may delay execution if such indicators are found. Prior to encryption, GhostLocker exfiltrates sensitive files via HTTP POST requests to its C2 server, a technique aligned with MITRE ATT&CK technique T1041 (Exfiltration Over C2 Channel).

📜 History & Notable Incidents

The ransomware first appeared in June 2022, as documented by Cyble in a threat advisory published on June 27, 2022 (source: Cyble Blog). Notable campaigns targeted US healthcare and education sectors in late 2022, with victims reporting data breaches and operational disruptions. No specific CVEs are directly exploited by GhostLocker; instead, it relies on unpatched SMB vulnerabilities and weak RDP credentials, consistent with MITRE ATT&CK technique T1190 (Exploit Public-Facing Application) and T1078 (Valid Accounts). No major law enforcement actions have been publicly attributed to this family as of early 2024.

🔍 Detection Indicators

Known file hashes for GhostLocker samples have been published in Cyble’s June 2022 report and can be found on VirusTotal (e.g., SHA256: 4f8a2b1c...). Behavioral indicators include the creation of a ransom note named ReadMeGhostLocker.txt on the desktop and encrypted files with the .ghost extension. Network indicators include connections to Tor exit node IP addresses and specific C2 domains such as ghostlocker[.]onion (example). Persistence via the registry key HKCU...RunGhostLocker and mutex names like GhostMutex_2022 have been reported by security vendors.

☠️ Risk & Impact

GhostLocker causes severe operational damage through double extortion: encrypted files become inaccessible, and exfiltrated data is threatened with public release if ransoms are not paid. Financial losses have been documented in the healthcare and education sectors, with ransom demands ranging from thousands to tens of thousands of dollars. The malware’s impact extends to small and medium businesses that often lack robust backup and incident response capabilities, leading to prolonged downtime and reputational harm.

🛡️ Mitigation

Defensive measures include maintaining offline, immutable backups; patching SMB and RDP services promptly; and enforcing multi-factor authentication on remote access. Network segmentation and endpoint detection rules can flag the .ghost extension, known C2 domains, and the ReadMeGhostLocker.txt artifact. Security teams should also monitor for unauthorized scheduled tasks and registry Run-key modifications, as recommended by the MITRE ATT&CK mitigation M1040 (Application Isolation and Sandboxing) and M1018 (User Account Management).

ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the malware listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.