Sarcoma Group Ransomware

Sarcoma Group Ransomware is a recently discovered ransomware that poses a serious threat to personal computers and corporate networks. This comprehensive guide will help you understand what Sarcoma Ransomware is, how it infects computers, and most importantly, how to completely remove it from your system using the specialized Trojan Killer tool.

Common Names	Alibaba: Ransom:Win64/SARCOMA.b2fd8562 AliCloud: Ransomware:Win/Seheq.Gen Antiy-AVL: Trojan[Ransom]/Win64.Ymir Microsoft: Ransom:Win64/Filecoder!MTB TrendMicro: Ransom.Win64.SARCOMA.SM
Type	Ransomware, File Encryptor
First Detected	2024
Platforms Affected	Windows 7, 8, 8.1, 10, 11, Windows Server
Infection Level	Critical
Data Risk	Extremely High – encrypts files, steals sensitive data, and demands ransom

What is Sarcoma Group Ransomware?

Sarcoma Group Ransomware is a sophisticated ransomware that encrypts files on an infected computer or network and demands payment for their recovery. Unlike simpler malware, Sarcoma uses advanced infiltration methods, including zero-day vulnerability exploitation, as demonstrated during the attack on Smart Media Group Bulgaria in October 2024.

Sarcoma Group employs double extortion tactics: in addition to encrypting files, the group also exfiltrates confidential data and threatens to publish it if the ransom isn’t paid. According to Microsoft Security Intelligence research, this approach significantly increases the likelihood of victims paying the ransom.

Unlike less sophisticated ransomware, Sarcoma Ransomware exploits system vulnerabilities for initial access and has more sophisticated methods of removing shadow copies and other backup mechanisms, making recovery without a decryption key more difficult.

Interesting Facts About Sarcoma Group Ransomware

• Sarcoma Group is a relatively new player in the ransomware market but has quickly gained a reputation through successful attacks on major targets.
• The group gained notoriety after attacking Smart Media Group Bulgaria using a zero-day vulnerability.
• Sarcoma uses a sophisticated command and control infrastructure, including multiple Tor sites for communication with victims.
• Cybersecurity experts note similarities between Sarcoma’s techniques and previously known ransomware groups, which may indicate a rebranding of an existing group.
• Unlike some other ransomware operators, Sarcoma Group actively targets companies in the advertising and media sector.

Sarcoma Infection Statistics

Based on data collected from various cybersecurity reports and our own threat intelligence:

• Sarcoma Group has conducted a series of successful attacks, during which more than 40 GB of confidential data was stolen.
• The average ransom demanded ranges from $50,000 to $500,000 in cryptocurrency.
• About 65% of Sarcoma attacks target companies in the media, advertising, and entertainment industries.
• Approximately 30% of victims pay the ransom due to the threat of confidential data publication.
• The group’s activity is observed predominantly in Europe, North America, and Asia.

How Sarcoma Ransomware Spreads

Sarcoma Group uses several advanced distribution methods:

• Exploitation of zero-day vulnerabilities in network infrastructure
• Phishing campaigns with malicious attachments
• Compromising remote access credentials (RDP, VPN)
• Implementation through compromised software providers
• Using remote monitoring and management tools (RMM)

Learn more about how ransomware work and spread to better protect your system.

Signs of Sarcoma Ransomware Infection

Pay attention to the following symptoms indicating a Sarcoma infection:

• Inability to open files that have received the .xp9Mq1ZD05 extension
• Appearance of the FAIL_STATE_NOTIFICATION.pdf notification file in folders with encrypted files
• Unusual network activity, especially outgoing to unknown domains
• Disabling or failure of backup and protection services
• Removal of Windows shadow copies and other recovery mechanisms
• Increased CPU load and disk space usage
• Unexpected system reboots or critical errors

Dangers of Sarcoma Ransomware

Sarcoma poses many serious threats to infected systems and organizations:

• File Encryption: Makes files inaccessible without a decryption key
• Data Theft: Exfiltration of confidential information before encryption
• Financial Losses: Demanding large ransom sums in cryptocurrency
• Reputational Damage: Threat of publishing stolen data
• Business Process Disruption: Interruption of normal organization operations
• Further Compromise: Creating backdoors for future access
• Network Propagation: Infection of other systems in the corporate environment

Comparing Sarcoma to Other Ransomware

Understanding how Sarcoma compares to other known ransomware helps better recognize its unique features and evolution in the malware ecosystem.

Sarcoma Ransomware represents a new generation of industry-targeted ransomware. Unlike mass campaigns, Sarcoma conducts targeted attacks with thorough target reconnaissance. Sarcoma’s main feature is its use of zero-day vulnerabilities for initial access, making traditional perimeter defense measures less effective. The group specializes in attacks against companies in the media and advertising industry, where data value and potential reputational damage are particularly high. Sarcoma applies advanced encryption methods that are practically impossible to break without a key and uses double extortion tactics to maximize pressure on victims. Technically, the program demonstrates a high degree of complexity, including multi-stage infection processes and detection evasion.

While not as technically advanced as some threats like LockBit 4.0 Ransomware which utilizes multi-threaded encryption and triple extortion tactics, Sarcoma Group compensates with its highly targeted approach and industry-specific knowledge when selecting victims.

TrickBot, while originally developed as a banking trojan, evolved into a platform often used to deliver ransomware. Unlike Sarcoma, TrickBot is usually the first stage of an attack rather than the final payload. It specializes in credential collection and establishing persistent access that can then be used to deploy ransomware. TrickBot has a modular architecture allowing operators to add various functionalities depending on the target. While both TrickBot and Sarcoma can be part of ransomware attacks, their roles and technical approaches differ significantly.

Emotet, similar to TrickBot, started as a banking trojan but developed into a multi-purpose malware delivery platform. Emotet typically spreads through phishing campaigns, using stolen email content to create convincing attacks. Unlike Sarcoma, which focuses on vulnerabilities for initial access, Emotet relies on social engineering and document macros. Emotet is often used as an initial entry point, followed by other malware, including ransomware. Compared to Sarcoma’s targeted approach, Emotet is typically used in broader, less targeted campaigns.

The distinguishing feature of Sarcoma in this landscape is its specialization in specific industries and high-tech approach to initial access. While many ransomware rely on phishing or brute-forcing credentials, Sarcoma’s use of zero-day vulnerabilities demonstrates the group’s high level of technical capabilities and resources. This makes Sarcoma an especially dangerous threat that requires advanced defense strategies.

How to Remove Sarcoma Ransomware

1. Removal Using Trojan Killer

Trojan Killer is specifically designed to remove complex trojans and ransomware, including Sarcoma:

1. Download and install Trojan Killer from the official website
2. Run a system scan:
   • Launch the program with administrator privileges
   • Select full system scan
   • Wait for the process to complete (may take 30-60 minutes due to Sarcoma’s complexity)
3. Review scan results:
   • The program will display a list of detected threats
   • Look for entries related to Sarcoma and its components
4. Remove detected threats:
   • Select all detected Sarcoma components
   • Click the “Remove Selected” button
5. Perform a second scan to ensure complete removal
6. Restart your computer to complete the removal process

2. Manual Removal (For Advanced Users)

Warning: Manual removal of Sarcoma is extremely difficult due to its advanced persistence mechanisms and analysis protection features. This approach should only be attempted by users with significant technical experience.

1. Disconnect the infected system from the network to prevent Sarcoma from spreading or communicating with command servers
2. Boot your computer in Safe Mode with Networking:
   • Press F8 during computer startup
   • Select “Safe Mode with Networking”
3. Identify and terminate Sarcoma processes:
   • Open Task Manager (Ctrl+Shift+Esc)
   • Look for suspicious processes, especially those with randomly generated names
   • End these processes
4. Remove Sarcoma files:
   • Check these common Sarcoma locations:
     • C:\Windows\System32\config\systemprofile\AppData\Roaming\
     • C:\Users\[username]\AppData\Roaming\
     • C:\Users\[username]\AppData\Local\
     • C:\ProgramData\
     • C:\Windows\Temp\
   • Look for folders with random names containing executable files
   • Delete these suspicious files and folders
5. Clean the registry:
   • Open Registry Editor (regedit)
   • Check these registry locations for suspicious entries:
     • HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
     • HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
     • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Shell
   • Look for values pointing to suspicious files identified earlier
   • Delete these registry entries
6. Remove malicious scheduled tasks:
   • Open Command Prompt as administrator
   • Type schtasks /query /fo LIST /v to list all scheduled tasks
   • Look for tasks with random names or that run suspicious files
   • Delete suspicious tasks using schtasks /delete /tn "TaskName" /f

3. What to Do with Encrypted Files

After removing Sarcoma Ransomware, your files will unfortunately remain encrypted. You have several options:

1. Using backups:
   • Restore data from regular backups stored outside the system
   • Check for shadow copies (if they haven’t been deleted by the malware)
2. Checking for decryptors:
   • Monitor Microsoft Security Intelligence resources for free decryptors
   • Remember that for new ransomware, decryptors may not be available for a long time
3. Making a ransom decision:
   • We do not recommend paying the ransom, as this:
     • Finances criminal activity
     • Does not guarantee data recovery
     • May make you a target for future attacks
   • If you are still considering paying the ransom, consult with cybersecurity experts and law enforcement

Preventing Sarcoma Ransomware Infection

Protection against Sarcoma requires a comprehensive security approach:

• Regularly update all operating systems and software
• Implement multi-factor authentication for all remote access
• Use network segmentation to limit potential spread
• Create regular backups following the 3-2-1 rule (three copies, on two different media, one off-site)
• Conduct employee training on phishing and social engineering
• Implement strong password policies and credential management
• Use EDR (Endpoint Detection and Response) solutions for early threat detection
• Limit access to critical systems using the principle of least privilege
• Consider using ransomware protection solutions

These protective measures will help guard not only against Sarcoma but also against other threats such as trojan downloaders and potentially unwanted applications that might create vulnerabilities in your system.

Advanced Technical Analysis of Sarcoma (For Security Professionals)

This section provides detailed technical information about Sarcoma’s architecture, internals, and detection methods for security researchers, threat hunters, and incident response professionals.

Sarcoma Infrastructure and Architecture

Sarcoma uses a sophisticated infrastructure for its operations:

Sarcoma’s command and control infrastructure uses a multi-layered architecture:

Component	Technical Details	Features
Communication Protocol	HTTPS with certificate pinning and multi-layer proxy chain	Use of one-time domains for communication
Server Structure	Multi-tiered architecture with front-end proxy servers	Use of secure hosting and .onion domain
Fallback Mechanism	Several hardcoded IP addresses	Use of cryptocurrency networks for alternative communication
Data Encryption	AES-256 for file encryption, RSA-4096 for keys	Unique keys for each victim

Technical Indicators of Compromise

Security researchers should monitor the following indicators associated with Sarcoma:

• MD5 hash of the sample: B7E0AF5DBB170D91C63B700D8B324203
• Encrypted file extension: .xp9Mq1ZD05
• Ransom note file: FAIL_STATE_NOTIFICATION.pdf
• Onion addresses:
  • sarcomabwgzv7ogiulwqfmlul6mjcxy6o3owuld4lqguvevf4kgp3lqd.onion
  • sarcomawmawlhov7o5mdhz4eszxxlkyaoiyiy2b5iwxnds2dmb4jakad.onion
• Network indicators: suspicious outgoing connections to the Tor network
• System anomalies: deletion of shadow copies, disabling of Windows services

Detection and Mitigation Methods

Security professionals can implement the following approaches to protect their organization:

• Command line monitoring: Detection of commands related to shadow copy deletion or security service disabling
• Network traffic analysis: Identification of unusual connections to Tor or unknown IP addresses
• Regular backups: Use of isolated storage inaccessible to encryption
• Network segmentation: Limiting malware spread between critical systems
• System updates: Addressing vulnerabilities that might be used for initial access

Mitigation Commands

For system administrators working with affected systems:

Sample Ransom Note

Below is an example of the contents of the FAIL_STATE_NOTIFICATION.pdf file created by Sarcoma Ransomware:

These technical details provide security professionals with the information needed to better understand, detect, and protect against Sarcoma Ransomware in their environment.

Frequently Asked Questions

Can Sarcoma attack my home computer?

While Sarcoma Group predominantly targets corporate networks and organizations, home users are also at risk. Attackers can use phishing emails or compromised websites to spread malware to personal computers. Home users often have fewer resources for detecting and responding to such attacks, making them vulnerable. For protection, it’s recommended to use reliable antivirus software, regularly update your operating system and programs, create backups of important data, and be cautious when opening email attachments or clicking on suspicious links.

What should I do if I’m already infected with Sarcoma Ransomware?

If your system is already infected, you need to act quickly. First, disconnect your computer from the internet to prevent further spread of the malware or data leakage. Then use specialized tools, such as Trojan Killer, to scan for and remove malicious components. Unfortunately, already encrypted files will likely remain inaccessible without a decryption key. Check the availability of Windows shadow copies or restore data from backups if you have them. If it’s a corporate environment, immediately contact your IT security team and consider involving incident response specialists. Paying the ransom is not recommended, as it doesn’t guarantee recovery of your data.

How do I know my files are encrypted by Sarcoma and not another ransomware?

There are several characteristic signs indicating infection specifically by Sarcoma. First, look at the extension of encrypted files – Sarcoma adds the .xp9Mq1ZD05 extension to files. Second, check for the presence of a notification file named FAIL_STATE_NOTIFICATION.pdf in folders with encrypted files. The content of this file is also characteristic – it usually mentions specific Tor addresses for communication: sarcomabwgzv7ogiulwqfmlul6mjcxy6o3owuld4lqguvevf4kgp3lqd.onion and sarcomawmawlhov7o5mdhz4eszxxlkyaoiyiy2b5iwxnds2dmb4jakad.onion. Also, Sarcoma typically mentions data theft before encryption (double extortion tactic) and gives a limited time to pay the ransom, after which it threatens to publish the stolen data.

Why does Sarcoma target media companies?

Sarcoma Group chooses media and advertising companies as primary targets for several reasons. First, these organizations often possess valuable data – customer information, marketing plans, intellectual property, and confidential materials that can be used for blackmail. Second, media companies typically depend on continuous access to their systems to meet tight publication deadlines, making them more vulnerable to ransomware time pressure tactics. Third, the public nature of media companies means that data leaks will lead to significant reputational damage, increasing the likelihood of ransom payment. Finally, some media organizations may have less mature cybersecurity systems compared to financial or government institutions, making them easier targets.

Are there free decryptors for Sarcoma Ransomware?

At the time of writing this article, there are no reliable free decryptors for Sarcoma Ransomware. Since Sarcoma uses modern encryption methods (a combination of asymmetric RSA-4096 and symmetric AES-256), breaking the encryption without a key is technically extremely difficult. Law enforcement agencies and security researchers continuously work on analyzing new ransomware, and decryptors sometimes become available if vulnerabilities in encryption implementation are discovered or keys fall into the hands of specialists. It’s recommended to periodically check Microsoft Security Intelligence resources and specialized security forums for up-to-date information on possible solutions. However, the most reliable recovery method remains pre-created backups.

Conclusion

Sarcoma Group Ransomware represents a serious threat to organizations and individuals. This advanced ransomware combines sophisticated infiltration techniques, powerful encryption, and double extortion tactics, making it particularly dangerous.

The best protection against Sarcoma and similar threats is a comprehensive approach to cybersecurity, including regular updates, multi-factor authentication, network segmentation, and most importantly, a reliable backup strategy. Remember that prevention is always more effective than treatment, especially when it comes to ransomware.

If you do encounter Sarcoma, decisive actions to isolate the system, remove the malware, and restore from backups are your best steps. Specialized tools such as Trojan Killer can help detect and remove malicious components, although encrypted files will likely require restoration from backups.

Stay vigilant, keep your systems up to date, and monitor for new threats in the constantly changing cyber threat landscape.