Iran Cybercriminals Exploit VPNs to Gain Network Access

The Department of Homeland Security (DHA) Cybersecurity Security and Infrastructure Security Agency (CISA) and the Federal Bureau of Investigation (FBI) released a Joint Cybersecurity Advisory Alert AA20-259A. The advisory details  Iranian malicious cyber activity targeting U.S. government agencies and other U.S.-based networks. The threat actors detailed in the advisory typically conduct cyberespionage attacks.

The Iranian cybercriminals are an advanced persistent threat (APT) group referred to as Pioneer Kitten. These state sponsored hackers are exploiting vulnerabilities in virtual private networks (VPN) to gain and maintain network access. This advisory analyzes the threat actor’s indicators of compromise (IOCs); and tactics, techniques, and procedures (TTPs); and exploited Common Vulnerabilities and Exposures (CVEs). 

The FBI says that Pioneer Kitten has the ability and likely the intention to attack victim networks with ransomware.

The Iranian state-sponsored hackers are exploiting Common Vulnerabilities and Exposures (CVEs) dealing with Pulse Secure virtual private network (VPN), Citrix NetScaler, and F5 vulnerabilities according to the joint advisory. “The threat actor conducts mass-scanning and uses tools, such as Nmap, to identify open ports. Once the open ports are identified, the threat actor exploits CVEs related to VPN infrastructure to gain initial access to a targeted network,” says CISA

Target Industries:

• Information technology
• Government
• Healthcare
• Financial
• Insurance
• Media sectors

Pioneer Kitten

Pioneer Kitten is a state sponsored criminal advanced persistent threat group. They work at the behest of the Islamic Republic of Iran and were first seen in 2017. These Iranian threat actors are tracked by their moniker Pioneer Kitten and UNC757. Pioneer Kitten primary motivation is cyber espionage.

Common tools used by Pioneer Kitten

The feds say that the Iranian threat actors commonly used a Citrix NetScaler remote access server using a publicly available exploit for CVE-2019-19781 to compromise a network.

• ChunkyTuna web shell for reverse connections to a server to exfiltrate data
• China Chopper web shell to create a backdoor for remote access
• FIRPC for tunneling Remote Desktop Protocol (RDP)
• Chisel for secure communications
• Angry IP Scanner to ping IP addresses

The threat actors also deployed other techniques to evade detection, gain credential access, and learn about the victims’ network environment

Cyber Attack Mitigation

Keep all software up to date with the latest security patches. CISA and FBI recommend implementing the following to defend against attacks.

• Patch the Citrix CVE-2019-19781 vulnerability which is the primary way the threat actors gain network access
• Follow the recommendations in CISA Alert AA20-031A
• Routinely audit configuration and patch management programs.
• Monitor network traffic for unexpected and unapproved protocols
• Grant users the lowest privilege for data access they need to work
• Use multi-factor authentication for all accounts

Read the CISA advisory for more recommendations and details