Okay, I can do that! Here’s a short, discursive article about Fog Ransomware based on the provided document, written in English and suitable for online publication:
Fog Ransomware emerged in April 2024 and quickly became a significant cyber threat, particularly for organizations in the United States. Unlike some ransomware groups that focus on specific sectors, Fog has demonstrated opportunistic behavior, hitting a range of industries, with a concerning emphasis on business services, technology firms, and educational institutions. Why these targets? Let’s break it down.
US focus: a strategic choice?
A striking aspect of Fog’s operations is its strong focus on US-based entities. Over half of its recorded victims are in the United States, which raises some interesting questions. Is this a deliberate strategic choice, or simply a reflection of better reporting practices in the US? Regardless, North American organizations need to be particularly vigilant.
Double extortion and data-driven targeting
Fog Ransomware operates using a double extortion model: encrypting files and stealing sensitive data. This explains the focus on business services and technology firms, as these organizations often handle vast amounts of client data, making them prime targets for data exfiltration and extortion. A successful attack on a service provider can have cascading effects, impacting multiple downstream organizations.
Tactics and techniques: a multi-stage attack
Fog’s attack process is multi-staged, starting with initial access gained through various means:
- Exploiting vulnerabilities in public-facing applications
- Weak RDP configurations
- Phishing emails
- Stolen credentials
Once inside, Fog establishes persistence and escalates privileges, often using tools like Mimikatz to steal credentials. Lateral movement is then used to identify high-value systems and data. Before encryption, sensitive data is exfiltrated and uploaded to attacker-controlled servers. A TOR-based data leak site is used to pressure victims. The final stage involves encrypting files and dropping a ransom note.
In 2025 this ransomware gang also began to claim data leak attacks, not ransomware, coming from thefts of Gitlab projects (source codes of large production companies).
Defense strategies: a multi-layered approach
Protecting against Fog Ransomware requires a comprehensive, multi-layered security strategy:
- Multi-Factor Authentication (MFA): enforce MFA across all user accounts.
- Regular updates and patching: keep all software up-to-date.
- Employee training: educate employees on recognizing phishing attempts.
- Endpoint Detection and Response (EDR) solutions: use EDR tools to identify and respond to malicious activities.
- Network Segmentation: divide your network into segments to limit lateral movement.
- Data backups: regularly back up data and store backups offline.
- Incident Response plan: develop and test a comprehensive incident response plan.
Key takeaways
Fog Ransomware is a sophisticated threat that requires a proactive and multi-faceted defense. Organizations must prioritize cybersecurity, implement robust security measures, and stay informed about the latest tactics and techniques used by ransomware groups. By taking these steps, businesses can reduce their risk of falling victim to Fog Ransomware and other evolving cyber threats.
Indicators of Compromise (IoCs)
| Indicator | Type | Description |
|---|---|---|
| f7c8c60172f9ae4dab9f61c28ccae7084da90a06 | SHA1 | Fog ransomware binary (lck.exe) |
| 507b26054319ff31f275ba44ddc9d2b5037bd295 | SHA1 | Fog ransomware binary (locker_out.exe) |
| e1fb7d15408988df39a80b8939972f7843f0e785 | SHA1 | Fog ransomware binary (fs.exe) |
| 83f00af43df650fda2c5b4a04a7b31790a8ad4cf | SHA1 | Fog ransomware binary (locker_out.exe) |
| 44a76b9546427627a8d88a650c1bed3f1cc0278c | SHA1 | Fog ransomware binary (mon.dll) |
| eeafa71946e81d8fe5ebf6be53e83a84dcca50ba | SHA1 | PsExec (psexesvc.exe) |
| 763499b37aacd317e7d2f512872f9ed719aacae1 | SHA1 | Advanced Port Scanner (advanced_port_scanner.exe) |
| 3477a173e2c1005a81d042802ab0f22cc12a4d55 | SHA1 | Advanced Port Scanner (advanced_port_scanner_2.5.3869.exe) |
| 90be89524b72f330e49017a11e7b8a257f975e9a | SHA1 | SharpShares (sharpshares(1).exe) |
| DESKTOP-7G1IC87 | Hostname | Threat actor’s hostname |
| Kali | Hostname | Threat actor’s hostname |
| VPS65CCB8B75352 | Hostname | Threat actor’s hostname |
| PACKERP-VUDV41R | Hostname | Threat actor’s hostname |
| readme.txt | Filename | Ransom note |
| DBgLog.sys | Filename | Log file created by ransomware binary |
| Veeam-Get-Creds.ps1 | Filename | PowerShell script used to obtain passwords from Veeam Backup and Replication Credentials Manager |
| PSEXESVC.exe | Filename | PsExec |
| netscan.exe | Filename | SoftPerfect Network Scanner |
| .flocked | File Extension | Appended file extension to encrypted files |
| .fog | File Extension | Appended file extension to encrypted files |
| 5.230.33[.]176 | IP Address | IP address used by the threat actor to login to VPN appliance |
| 77.247.126[.]200 | IP Address | IP address used by the threat actor to login to VPN appliance |
| 107.161.50[.]26 | IP Address | IP address used by the threat actor to login to VPN appliance |