FortiOS & FortiProxy - Out-of-bound-write in sslvpnd Vulnerability!!

[duahimanshu]

Hello Experts, 

thanks in advance. 

I recently came across an advisory from Fortinet regarding a vulnerability with a CVSS score of 7.1  They recommend upgrading to version 7.2.4 or applying a workaround.

The workaround suggested involves disabling the "Host Check," "Restrict to Specific OS Versions," and "MAC address host checking" in the SSLVPN portal configuration. However, my concern is that by disabling these checks, are we not potentially exposing ourselves to other security issues? It seems that these settings essentially bypass the checks before allowing SSLVPN connections.

PSIRT Advisories | FortiGuard

workaround

config vpn ssl web portal
edit "full-access"
set os-check disable
set host-check none
set mac-addr-check disable
end

[AEK]

They mean if you enable these checks then you will be exposed to more serious breaches than when disabling them.

You can disable these checks and harden your VPN with other features till you update your FortiOS.

[DWonker]

Try using an earlier version of FortiOS.  This same problem happened to me and I fixed it easily :beaming_face_with_smiling_eyes: by using version 5.2.  The FortiShield has a very strong VPN.  I recommend not updating your FortiOS, and just keeping it at an earlier version.