Conti Ransomware Group

Spearphishing: Highly targeted emails with malicious attachments (e.g., Word documents with embedded scripts) or links, often dropping initial access malware like TrickBot, BazarLoader, or IcedID.

Exploiting Vulnerabilities: Targeting known vulnerabilities in internet-facing systems like VPNs, RDP, or web applications (e.g., FortiGate SSL VPN flaws, Microsoft Exchange Server flaws - ProxyShell, PrintNightmare CVE-2021-34527, Zerologon CVE-2020-1472). CISA warns of active exploitation and understanding vulnerability assessments is key to prevention.

Stolen Credentials: Using compromised Remote Desktop Protocol (RDP) or VPN credentials, often purchased from Initial Access Brokers (IABs).

Malware Distribution Networks: Leveraging existing botnets like Emotet or ZLoader for distribution.

Command and Control (C2): Establishing C2 channels using frameworks like Cobalt Strike or custom backdoors (e.g., BazarBackdoor). They often used numerous, victim-specific C2 servers.

Credential Harvesting: Employing tools like Mimikatz or Windows Sysinternals (e.g., ProcDump) to steal credentials, including domain administrator accounts. Kerberos attacks were also observed.

Discovery: Mapping the network using native Windows tools, Active Directory queries, and network scanning tools (like Router Scan) to identify valuable systems, domain controllers, file shares, and backups.

Lateral Movement: Spreading through the network using stolen credentials via RDP, PsExec, or exploiting SMB vulnerabilities (like EternalBlue remnants) to deploy Cobalt Strike beacons or the ransomware payload itself.

Antivirus Evasion: Using custom packers or crypters (like the one developed by indicted member Maksim Galochkin) to obfuscate malware and bypass AV detection. Terminating AV processes and disabling real-time monitoring features like Windows Defender.

Deleting Backups: Using scripts or built-in Windows utilities (vssadmin.exe) to delete Volume Shadow Copies, hindering system recovery.

Terminating Services: Stopping services related to databases, security software, and backups using Windows Restart Manager or taskkill commands to ensure files are not locked during encryption.

Data Theft: Before encryption, attackers exfiltrated large volumes of sensitive data using tools like rclone or MegaSync to cloud storage controlled by Conti.

Encryption: Deployed the Conti ransomware payload, which used a fast implementation of AES-256 (later switching to ChaCha for potentially better speed/evasion) with RSA for key protection. It utilized multiple CPU threads (up to 32) for rapid encryption of files on local drives and accessible network shares (SMB). It typically appended a .CONTI or similar extension and dropped ransom notes (readme.txt or CONTI_README.txt) in directories. Files critical to system operation (like .exe, .dll, .sys) were often excluded to keep the system usable for ransom negotiation.

Extortion: Threatened to publish the stolen data on their "Conti News" leak site if the ransom was not paid, adding pressure beyond the decryption key demand. They were known for aggressive negotiation tactics and sometimes leaked data even after partial payment or during negotiations.

Target Industries: While opportunistic, Conti showed a propensity for targeting:

Target Regions: Conti operated globally but had a significant focus on organizations in North America (especially the United States, which saw over 40% of attacks) and Western Europe. They generally avoided targeting entities within the Commonwealth of Independent States (CIS), a common practice among Russia-based cybercrime groups.

Impact: Beyond data encryption and theft, Conti attacks caused widespread operational disruption, significant financial losses (ransom payments, recovery costs, lost revenue), reputational damage, and in the case of healthcare and government targets, disruption of critical public services. The trend of healthcare data breaches has surged, impacting millions of patient records.

Ireland's Health Service Executive (HSE) (May 2021): A devastating attack that crippled Ireland's national healthcare IT systems for weeks, forcing widespread cancellations of appointments and diagnostics. Conti demanded a $20 million ransom but later provided a decryptor for free (though the disruption was already immense), possibly due to public backlash. Data was still exfiltrated.

Costa Rican Government (April-May 2022): A series of attacks targeting multiple government ministries (Finance, Labor, Social Security, etc.), causing significant disruption to foreign trade, tax systems, and government services. The newly inaugurated President declared a national emergency. Conti demanded $10 million, later raising it to $20 million. This attack occurred shortly before the group's dissolution.

JVCKenwood (September 2021): The electronics giant was attacked, with Conti demanding a $7 million ransom and later leaking data after negotiations reportedly failed.

Scripps Health (May 2021): A major healthcare provider in Southern California suffered a significant outage affecting patient care systems, electronic health records, and scheduling. The attack cost Scripps Health nearly $113 million. Several Conti members were later indicted in connection with this attack.

Nordic Choice Hotels (December 2021): Major hotel chain in Scandinavia hit, impacting booking systems.

Various Local Governments & School Districts (US): Conti frequently targeted smaller public entities often perceived as having weaker security postures.

Patch Management: Aggressively patch known vulnerabilities, especially those in internet-facing systems (VPNs, RDP, Exchange) frequently exploited by ransomware groups (e.g., ProxyShell, PrintNightmare, Zerologon). A solid patch management strategy is essential.

Multi-Factor Authentication (MFA): Enforce MFA on all remote access points (VPN, RDP), cloud services, and critical internal accounts, especially administrative ones.

Security Awareness Training: Educate users to recognize and report phishing attempts, suspicious links, and malicious attachments. Conduct regular phishing simulations.

Network Segmentation: Segment networks to limit lateral movement. Isolate critical systems and control traffic flow between segments.

Principle of Least Privilege: Ensure users and service accounts only have the permissions necessary for their roles. Restrict administrative privileges tightly.

Email Security: Implement robust email filtering solutions to block spam, phishing emails, and malicious attachments. Knowing the different types of phishing attacks helps in creating effective training.

Disable Unnecessary Services: Harden endpoints by disabling unused ports and services like RDP if not essential, or limiting RDP access via firewalls and jump boxes.

Endpoint Detection and Response (EDR/XDR): Deploy advanced EDR/XDR solutions capable of detecting malicious behaviors (e.g., credential dumping, lateral movement, suspicious script execution) associated with ransomware TTPs, not just known signatures. Monitor for tools like Cobalt Strike, Mimikatz, PsExec, and rclone.

Network Monitoring: Monitor network traffic for anomalies, C2 communications, large data transfers (exfiltration), and unusual SMB activity. Use Intrusion Detection/Prevention Systems (IDPS).

Log Management & SIEM: Centralize logging from endpoints, servers, firewalls, and applications. Use a Security Information and Event Management (SIEM) system to correlate events and detect suspicious patterns. Monitor for Active Directory changes and credential abuse.

Threat Intelligence: Stay informed about current ransomware TTPs, IOCs (Indicators of Compromise like malicious IPs/domains, file hashes), and threat actor activities through threat intelligence feeds and security advisories (e.g., CISA alerts).

Incident Response Plan (IRP): Develop, maintain, and regularly test a comprehensive IRP specifically addressing ransomware scenarios. Ensure roles and responsibilities are clear.

Backups: Implement a robust backup strategy (e.g., 3-2-1 rule). Ensure backups are immutable, stored offline or air-gapped, and tested regularly for recoverability. Protect backup infrastructure itself from compromise.

Isolation: Have procedures to quickly isolate infected systems from the network to prevent further spread.

Containment & Eradication: Follow the IRP to contain the infection, identify the scope, eradicate the malware, and restore systems safely.

Consult Experts: Engage with cybersecurity incident response professionals and legal counsel. Consult law enforcement before considering any ransom payment (which is generally discouraged and does not guarantee data recovery or non-disclosure). Having a proper cyber incident response plan is extremely vital.