In March 2021 it was observed Advanced Persistent Threat (APT) actors scanning devices on ports 4443, 8443, and 10443 for CVE-2018-13379, and enumerated devices for CVE-2020-12812 and CVE-2019-5591. It is likely that the APT actors are scanning for these vulnerabilities to gain access to multiple government, commercial, and technology services networks. APT actors have historically exploited critical vulnerabilities to conduct distributed denial-of-service (DDoS) attacks, ransomware attacks, structured query language (SQL) injection attacks, spear phishing campaigns, website defacements, and disinformation campaigns.
The FBI and CISA have information indicating APT actors are using multiple CVEs to exploit Fortinet FortiOS vulnerabilities. It is believed the APT actors are likely exploiting these Fortinet FortiOS vulnerabilities—CVE 2018-13379, CVE-2020-12812, and CVE-2019-5591—to gain access to multiple government, commercial, and technology services networks. The APT actors may be using any or all of these CVEs to gain access to networks across multiple critical infrastructure sectors to gain access to key networks as pre-positioning for follow-on data exfiltration or data encryption attacks. APT actors may use other CVEs or common exploitation techniques—such as spearphishing—to gain access to critical infrastructure networks to pre-position for follow-on attacks.
Organizations should take the following:
- Immediately patch CVEs 2018-13379, 2020-12812, and 2019-5591.
- If FortiOS is not used by your organization, add key artifact files used by FortiOS to your organization’s execution deny list. Any attempts to install or run this program and its associated files should be prevented.
- Regularly back up data, air gap, and password protect backup copies offline. Ensure copies of critical data are not accessible for modification or deletion from the primary system where the data resides.
- Implement network segmentation.
- Require administrator credentials to install software.
- Implement a recovery plan to restore sensitive or proprietary data from a physically separate, segmented, secure location (e.g., hard drive, storage device, the cloud).
- Install updates/patch operating systems, software, and firmware as soon as updates/patches are released.
- Use multifactor authentication where possible.
- Regularly change passwords to network systems and accounts, and avoid reusing passwords for different accounts. Implement the shortest acceptable timeframe for password changes.
- Disable unused remote access/Remote Desktop Protocol (RDP) ports and monitor remote access/RDP logs.
- Audit user accounts with administrative privileges and configure access controls with least privilege in mind.
- Install and regularly update antivirus and anti-malware software on all hosts.
- Consider adding an email banner to emails received from outside your organization.
- Disable hyperlinks in received emails.
- Focus on awareness and training. Provide users with training on information security principles and techniques, particularly on recognizing and avoiding phishing emails.