Gunra Ransomware’s Double‑Extortion Playbook and Global Impact

Gunra Ransomware, has surfaced as a formidable threat in April 2025, targeting Windows systems across industries such as real estate, pharmaceuticals, and manufacturing.

As reported by CYFIRMA, this ransomware employs a sophisticated double-extortion strategy, encrypting victims’ data while exfiltrating sensitive information to coerce payments.

With documented attacks in Japan, Egypt, Panama, Italy, and Argentina, Gunra’s global reach underscores its potential to disrupt business operations on a massive scale.

The malware, derived from Conti Ransomware and coded in C/C++, appends a “.ENCRT” extension to encrypted files and drops a ransom note named “R3ADM3.txt” in affected directories, guiding victims to a Tor-based negotiation portal for ransom demands.

Technical Sophistication and Evasion Tactics

Gunra Ransomware showcases advanced malicious behaviors designed to evade detection and maximize impact.

Upon infection, it enumerates running processes, deletes shadow copies via Windows Management Instrumentation (WMI), and gathers system information for targeted encryption.

Its anti-analysis capabilities include the use of the IsDebuggerPresent API to detect debuggers like x64dbg and WinDbg, alongside process manipulation through GetCurrentProcess and TerminateProcess functions for privilege escalation and code injection.

The ransomware employs FindNextFileExW and related functions to discover and encrypt files with extensions like .docx, .pdf, and .jpg, ensuring comprehensive data lockdown.

Beyond encryption, Gunra threatens to leak stolen data on underground forums within a tight five-day deadline, amplifying pressure on victims through its Tor-hosted extortion platform styled akin to messaging apps like WhatsApp, complete with roles like “Manager” for negotiations.

Its alignment with the MITRE ATT&CK framework reveals tactics spanning execution (T1047: WMI), persistence (T1542: Bootkit), privilege escalation (T1055: Process Injection), defense evasion (T1027: Obfuscated Files), and impact (T1486: Data Encryption), painting a picture of a highly coordinated threat aimed at financial gain.

Gunra’s attack lifecycle exemplifies modern ransomware sophistication, starting with reconnaissance to map system processes, followed by disabling recovery options through shadow copy deletion, and culminating in encryption and ransom note distribution.

This multi-stage approach not only disrupts operations but also hinders reverse engineering efforts, making it a critical concern for cybersecurity teams.

CYFIRMA recommends robust mitigations, including advanced Endpoint Detection and Response (EDR) systems to monitor for abnormal behaviors like WMI abuse or unusual file modifications, alongside regular offline backups, anti-ransomware software, and network segmentation to curb lateral movement.

Organizations are urged to limit administrative privileges, monitor Tor-related traffic, and educate employees on phishing tactics to prevent initial infiltration.

As Gunra Ransomware continues to evolve, staying updated with threat intelligence and deploying proactive cybersecurity measures remain paramount to safeguarding critical data and infrastructure from this insidious global threat.

Indicators of Compromise (IOCs)