CVE-2020-12820 Information

Description

Under non-default configuration a stack-based buffer overflow in FortiOS version 6.0.10 and below version 5.6.12 and below may allow a remote attacker authenticated to the SSL VPN to crash the FortiClient NAC daemon (fcnacd) and potentially execute arbitrary code via requesting a large FortiClient file name. We are not aware of proof of concept code successfully achieving the latter.

Reference

https://fortiguard.fortinet.com/psirt/FG-IR-20-083