FortiOS / FortiProxy / FortiSwitchManager - Authentication bypass on 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 &lt;MY IP&gt; &lt;MY SUBNET end

Please contact customer support for assistance.

FortiSwitchManager:

DIsable HTTP/HTTPS administrative interface

Please contact customer support for assistance.

Affected Products

FortiOS versions 5.x, 6.x are NOT impacted.
FortiOS version 7.2.0 through 7.2.1
FortiOS version 7.0.0 through 7.0.6
FortiProxy version 7.2.0
FortiProxy version 7.0.0 through 7.0.6
FortiSwitchManager version 7.2.0
FortiSwitchManager version 7.0.0

Solutions

Please upgrade to FortiOS version 7.2.2 or above
Please upgrade to FortiOS version 7.0.7 or above
Please upgrade to FortiProxy version 7.2.1 or above
Please upgrade to FortiProxy version 7.0.7 or above
Please upgrade to FortiSwitchManager version 7.2.1 or above
Please upgrade to FortiSwitchManager version 7.0.1 or above

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