AGILITY NETWORK SERVICES INC. HAS PROVIDED A VERY GENERAL DESCRIPTION OF EACH FROM THE CVE SITE (A THIRD PARTY SPONSORED BY THE DEPARTMENT OF HOMELAND SECURITY):
CVE-2018-13379 Has a description of: An Improper Limitation of a Pathname to a Restricted Directory (“Path Traversal”) in Fortinet FortiOS 6.0.0 to 6.0.4, 5.6.3 to 5.6.7 and 5.4.6 to 5.4.12 under SSL VPN web portal allows an unauthenticated attacker to download system files via special crafted HTTP resource requests.
CVE-2020-12812 Has a description of: An improper authentication vulnerability in SSL VPN in FortiOS 6.4.0, 6.2.0 to 6.2.3, 6.0.9 and below may result in a user being able to log in successfully without being prompted for the second factor of authentication (FortiToken) if they changed the case of their username.
CVE-2019-5591 Has a description of: A Default Configuration vulnerability in FortiOS may allow an unauthenticated attacker on the same subnet to intercept sensitive information by impersonating the LDAP server.
About CVE: The mission of the CVE Program is to identify, define, and catalog publicly disclosed cybersecurity vulnerabilities. There is one CVE Record for each vulnerability in the catalog. The vulnerabilities are discovered then assigned and published by organizations from around the world that have partnered with the CVE Program. Partners publish CVE Records to communicate consistent descriptions of vulnerabilities. Information technology and cybersecurity professionals use CVE Records to ensure they are discussing the same issue, and to coordinate their efforts to prioritize and address the vulnerabilities.
CISA encourages users and administrators to review Joint CSA AA21-092A: APT Actors Exploit Vulnerabilities to Gain Initial Access for Future Attacks and implement the recommended mitigations.