Rhysida

MITRE ATT&CK does not currently catalogue Rhysida, so this is our assessment of the techniques it uses, drawn from public reporting. The techniques themselves, and every "what that means" definition below, come from MITRE ATT&CK v19.2. Confidence: medium. Treat it as orientation, not attribution.

1. T1059.001 PowerShell Execution

   What they do: rhysida executes malicious commands via PowerShell scripts to stage payloads and manipulate system behavior.

   What that means: Adversaries may abuse PowerShell commands and scripts for execution.

2. T1547.001 Registry Run Keys / Startup Folder PersistencePrivilege Escalation

   What they do: rhysida modifies registry run keys to ensure malware execution upon system reboot for persistence.

   What that means: Adversaries may achieve persistence by adding a program to a startup folder or referencing it with a Registry run key.

3. T1685 Disable or Modify Tools Defense Impairment

   What they do: rhysida disables antivirus tools and security software to prevent detection and hinder incident response efforts.

   What that means: Adversaries may disable, degrade, or tamper with security tools or applications (e.g., endpoint detection and response (EDR) tools, intrusion detection systems (IDS), antivirus, logging agents, sensors, etc.) to impair or reduce visibility of defensive capabilities.

4. T1027.016 Junk Code Insertion Stealth

   What they do: rhysida inserts junk code into legitimate binaries to evade static analysis and detection by security tools.

   What that means: Adversaries may use junk code / dead code to obfuscate a malware’s functionality.

5. T1070.004 File Deletion Stealth

   What they do: rhysida deletes Volume Shadow Copies and backup directories via vssadmin and native commands to eliminate recovery options.

   What that means: Adversaries may delete files left behind by the actions of their intrusion activity.

6. T1018 Remote System Discovery Discovery

   What they do: rhysida performs remote system discovery to identify additional hosts for lateral movement within the victim network.

   What that means: Adversaries may attempt to get a listing of other systems by IP address, hostname, or other logical identifier on a network that may be used for Lateral Movement from the current system.

7. T1135 Network Share Discovery Discovery

   What they do: rhysida scans network shares using Windows tools to identify victim files and expand foothold across the network.

   What that means: Adversaries may look for folders and drives shared on remote systems as a means of identifying sources of information to gather as a precursor for Collection and to identify potential systems of interest for Lateral Movement.

8. T1567.002 Exfiltration to Cloud Storage Exfiltration

   What they do: rhysida exfiltrates stolen data via encrypted channels to pressure victims into paying ransom.

   What that means: Adversaries may exfiltrate data to a cloud storage service rather than over their primary command and control channel.

9. T1486 Data Encrypted for Impact Impact

   What they do: rhysida encrypts victim files using custom ransomware binaries targeting critical data across affected systems.

   What that means: Adversaries may encrypt data on target systems or on large numbers of systems in a network to interrupt availability to system and network resources.

Software Rhysida has been seen using, grouped by what it is used for. Legitimate administration tools appear here because these actors routinely abuse them — presence in this list is not itself malicious.

Tool data from Ransomware Tool Matrix by BushidoUK, licensed CC BY 4.0. Grouped by purpose and matched to this group by Dark Eye.

The note this group leaves on a compromised machine. Click a filename to read it.

Critical Breach Detected - Immediate Response Required

Dear company,

This is an automated alert from cybersecurity team Rhysida. An unfortunate situation has arisen - your digital ecosystem has been compromised, and a substantial amount of confidential data has been exfiltrated from your network. The potential ramifications of this could be dire, including the sale, publication, or distribution of your data to competitors or media outlets. This could inflict significant reputational and financial damage.

However, this situation is not without a remedy.

Our team has developed a unique key, specifically designed to restore your digital security. This key represents the first and most crucial step in recovering from this situation. To utilize this key, visit our secure portal: rhysidafohrhyy2aszi7bm32tnjat5xri65fopcxkdfxhi4tidsg7cad.onion with your secret key [snip]

It's vital to note that any attempts to decrypt the encrypted files independently could lead to permanent data loss. We strongly advise against such actions.

Time is a critical factor in mitigating the impact of this breach. With each passing moment, the potential damage escalates. Your immediate action and full cooperation are required to navigate this scenario effectively.

Rest assured, our team is committed to guiding you through this process. The journey to resolution begins with the use of the unique key. Together, we can restore the security of your digital environment.

Best regards

Ransom-note text from RansomLook, licensed CC BY 4.0.