PSIRTOut-of-bound-write in sslvpnd
Summary
An out-of-bounds write vulnerability [CWE-787] in sslvpnd of FortiOS and FortiProxy may allow an authenticated attacker to achieve arbitrary code execution via specifically crafted requests.
| Version | Affected | Solution |
|---|---|---|
| FortiOS 7.4 | Not affected | Not Applicable |
| FortiOS 7.2 | 7.2.0 through 7.2.3 | Upgrade to 7.2.5 or above |
| FortiOS 7.0 | 7.0.0 through 7.0.10 | Upgrade to 7.0.11 or above |
| FortiOS 6.4 | 6.4.0 through 6.4.11 | Upgrade to 6.4.12 or above |
| FortiOS 6.2 | 6.2.0 through 6.2.13 | Upgrade to 6.2.14 or above |
| FortiOS 6.0 | 6.0.0 through 6.0.16 | Upgrade to 6.0.17 or above |
| FortiProxy 7.2 | 7.2.0 through 7.2.1 | Upgrade to 7.2.2 or above |
| FortiProxy 7.0 | 7.0.0 through 7.0.7 | Upgrade to 7.0.8 or above |
| FortiProxy 2.0 | 2.0 all versions | Migrate to a fixed release |
| FortiProxy 1.2 | 1.2 all versions | Migrate to a fixed release |
| FortiProxy 1.1 | 1.1 all versions | Migrate to a fixed release |
| FortiProxy 1.0 | 1.0 all versions | Migrate to a fixed release |
Workaround:
Disable "Host Check", "Restrict to Specific OS Versions" and "MAC address host checking" in sslvpn portal configuration. For example for "full-access" sslvpn portal:
config vpn ssl web portal
edit "full-access"
set os-check disable
set host-check none
set mac-addr-check disable
end
Acknowledgement
Internally discovered and reported by Gwendal Guégniaud of Fortinet Product Security team in the frame of an internal audit of the SSL-VPN component.Timeline
2023-04-13: Initial publication2023-05-15: add a new fixed version 6.0.17 for FortiOS