Target Audience: SOC, IR Teams, CISOs
Risk Level: High - multi-sector, double extortion, cross-region
Overview
Lynx (now rebranded Sinobi) is an aggressive RaaS actor known since mid-2024. With roots in INCRansomware, it targets critical sectors (energy, manufacturing, legal) using phishing, service killing, and data exfiltration leading to double extortion
Key Threat Indicators
- Phishing emails with malicious attachments.
- Unusual process terminations: SQL, Veeam, Exchange.
- Deletion of Windows shadow copies.
- Suspicious AES encryption patterns and file renaming.
- Outbound data transfers preceding encryption.
Recommended Mitigations
- Enforce MFA on all privileged accounts.
- Regularly patch AV, backup (Veeam, ..), OS, and applications.
- Monitor process-level anomalies, especially service terminations.
- Deploy behavioral EDR/UEBA to detect lateral movement and encryption bursts.
- Segment networks to protect critical assets (SDN, VLANs).
- Maintain isolated, immutable backups, test recovery regularly.
- Monitor TOR sites for suspected data leaks.
Detection Strategies
- Alert on process termination via Restart Manager APIs.
- Flag deletion of shadow copies ("vssadmin delete shadows").
- Monitor large outbound files sent pre-encryption.
- Track unexpected service shutdowns.
Response Actions
- Immediately isolate affected hosts from network.
- Initiate full forensic investigation of ransomware digging.
- Identify and remove backdoor accounts or persistent mechanisms.
- Notify stakeholders and law enforcement where required.
- Begin encrypted recovery from clean backups; validate integrity.