CVE-2020-9291: 
FortiClient vulnerability analysis and mitigation

An Insecure Temporary File vulnerability (CVE-2020-9291) was discovered in FortiClient for Windows version 6.2.1 and below. The vulnerability was disclosed on May 25, 2020, and was discovered by Lasse Trolle Borup of Danish Cyber Defence (CERT-EU).

The vulnerability allows a local user to gain elevated privileges by exhausting the pool of temporary file names combined with a symbolic link attack. The vulnerability has received a CVSS v3.1 base score of 7.8 (HIGH) from NIST with vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H, while Fortinet assigned it a score of 6.3 (MEDIUM) with vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L (NVD).

If successfully exploited, this vulnerability could allow an authenticated local attacker to gain elevated privileges on the affected system, potentially leading to complete system compromise with high impacts on confidentiality, integrity, and availability (CERT-EU).

The vulnerability requires local access and successful authentication to the system. At the time of disclosure, there was no publicly available exploit code (CERT-EU).

The primary mitigation is to upgrade to FortiClient for Windows version 6.2.2 or above. If upgrading is not immediately possible, it is recommended to restrict access to affected computers only to trusted individuals (CERT-EU).