Authentication bypass in administrative interface

Summary

An authentication bypass using an alternate path or channel vulnerability [CWE-288] in FortiOS, FortiProxy and FortiSwitchManager may allow an unauthenticated attacker to perform operations on the administrative interface via specially crafted HTTP or HTTPS requests.

Exploitation Status:

Fortinet is aware of an instance where this vulnerability was exploited, and recommends immediately validating your systems against the following indicator of compromise in the device's logs:

user=Local_Process_Access

Please contact customer support for assistance.

UPDATE:

Fortinet is aware of instances where this vulnerability was exploited to download the config file from the targeted devices, and to add a malicious super_admin account called 'fortigate-tech-support':

# show system admin
edit fortigate-tech-support
set accprofile super_admin
set vdom root
set password ENC [...]
next

Please contact customer support for assistance.

Workaround:

FortiOS:

Disable HTTP/HTTPS administrative interface

OR

Limit IP addresses that can reach the administrative interface:

config firewall address
edit my_allowed_addresses
set subnet <MY IP> <MY SUBNET>
end

Then create an Address Group:

config firewall addrgrp
edit MGMT_IPs
set member my_allowed_addresses
end

Create the Local in Policy to restrict access only to the predefined group on management interface (here: port1):

config firewall local-in-policy
edit 1
set intf port1
set srcaddr MGMT_IPs
set dstaddr all
set action accept
set service HTTPS HTTP
set schedule always
set status enable
next
edit 2
set intf any
set srcaddr all
set dstaddr all
set action deny
set service HTTPS HTTP
set schedule always
set status enable
end

If using non default ports, create appropriate service object for GUI administrative access:

config firewall service custom
edit GUI_HTTPS
set tcp-portrange admin-sport
next
edit GUI_HTTP
set tcp-portrange admin-port
end

Use these objects instead of 'HTTPS HTTP' in the local-in policy 1 and 2 below.

UPDATE: When using an HA reserved management interface, the local in policy needs to be configured slightly differently - please see:

https://community.fortinet.com/t5/FortiGate/Technical-Tip-How-to-configure-a-local-in-policy-on-a-HA/ta-p/222005

https://community.fortinet.com/t5/FortiGate/Technical-Tip-How-to-configure-a-local-in-policy-on-a-HA/ta-p/222005

Please contact customer support for assistance.

FortiProxy:

Disable HTTP/HTTPS administrative interface

OR

For FortiProxy VM all versions or FortiProxy appliance 7.0.6:

Limit IP addresses that can reach the administrative interface (here: port1):

config system interface
edit port1
set dedicated-to management
set trust-ip-1 <MY IP> <MY SUBNET>
end

Please contact customer support for assistance.

FortiSwitchManager:

DIsable HTTP/HTTPS administrative interface

Please contact customer support for assistance.

Please upgrade to FortiOS version 7.0.5 B8001 or above for FG6000F and 7000E/F series platforms