CISA Warns Of Hackers Exploiting Multiple Flaws In Ivanti VPN

Threat actors target and abuse VPN flaws because VPNs are often used to secure sensitive data and communications, making them valuable targets for exploitation. 

By exploiting the VPN flaws, threat actors can gain unauthorized access to networks, intercept confidential data, and launch various cyber attacks.

CISA (The Cybersecurity and Infrastructure Security Agency), along with the following partners, recently warned that hackers are actively exploiting multiple vulnerabilities (CVE-2023-46805, CVE-2024-21887, and CVE-2024-21893) in Ivanti VPN:-

• Federal Bureau of Investigation (FBI)
• Multi-State Information Sharing & Analysis Center (MS-ISAC)
• Australian Signals Directorate’s Australian Cyber Security Centre (ASD’s ACSC)
• United Kingdom National Cyber Security Centre (NCSC-UK)
• Canadian Centre for Cyber Security (Cyber Centre), a part of the Communications Security Establishment
• New Zealand National Cyber Security Centre (NCSC-NZ)
• CERT-New Zealand (CERT NZ)

CISA Warns Hackers Exploiting Ivanti VPN

The Ivanti gateways have serious vulnerabilities impacting all supported versions (9.x and 22.x), enabling attackers to bypass authentication, execute commands, and evade detection.

CISA found Ivanti’s ICT systems failed to detect the compromise, due to which they urged network defenders to assume credential compromise and perform the following tasks:-

• Hunt for malicious activity
• Run updated ICT
• Apply patches

Organizations should be wary of rootkit-level persistence even after factory resets, as sophisticated threat actors may remain undetected for extended periods. 

Due to significant risks, it’s strongly advised to reconsider using Ivanti Connect Secure and Policy Secure gateways in enterprise environments.

CISA responded to Ivanti vulnerabilities by detecting the threat actors exploiting CVEs to implant web shells and harvest credentials. 

Post-compromise threat actors used Ivanti-native tools like freerdp and SSH for lateral movement, which led to full domain compromises. 

Ivanti’s ICT failed to detect the compromise, while the integrity checker and forensic analysis proved unreliable. Cybercriminals could erase traces by highlighting the unreliability of the ICT scans in indicating compromise. 

Independent research validated Ivanti’s ICT insufficiency that allows cyber threat actors to persist even after factory resets and upgrades.

Mitigations

Here below, we have mentioned all the mitigations provided by the cybersecurity researchers:-

• Make sure to choose VPNs wisely and avoid proprietary protocols or non-standard features.
• Secure remote access tools.
• Restrict outbound connections on SSL VPNs for essential services.
• Use low-privilege accounts for LDAP bind in SSL VPNs with AD/LDAP authentication.
• Allow SSL VPN access for unprivileged accounts only to reduce credential exposure.
• Keep OS, software, and firmware updated.
• Minimize Remote Desktop Protocols and remote desktop service usage.
• Configure Windows Registry for UAC approval on PsExec for admin tasks to curb lateral movement.
• Develop a recovery plan with multiple copies of sensitive data in a secure location.
• Enforce the NIST password policy for all password-based logins.

You can block malware, including Trojans, ransomware, spyware, rootkits, worms, and zero-day exploits, with Perimeter81 malware protection. All are incredibly harmful, can wreak havoc, and damage your network.