Fortinet FortiOS < 5.2.15, 5.4.0 < 6.0.5 SSL VPN web portal Host Header Redirection (FG-IR-19-002)

medium Nessus Plugin ID 125889
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The remote host is affected by a host header redirection vulnerability.


The remote host is running a version of FortiOS prior to 5.2.15 or 5.4.0 prior to 6.0.5. It is, therefore, affected by a host header redirection vulnerability in the SSL VPN web portal due to a failure to properly validate HTTP request headers. An unauthenticated, remote attacker can exploit this, via a specially crafted HTTP request to redirect SSL VPN web portal users to arbitrary web domains.


Upgrade to Fortinet FortiOS version to 5.2.15, 6.0.5 or 6.2.0 or later. Alternatively, apply one of the workarounds outlined in the linked advisory

See Also

Plugin Details

Severity: Medium

ID: 125889

File Name: fortios_FG-IR-19-002.nasl

Version: 1.4

Type: local

Family: Firewalls

Published: 6/14/2019

Updated: 4/29/2021

Dependencies: fortinet_version.nbin

Configuration: Enable paranoid mode

Risk Information

CVSS Score Source: CVE-2018-13384


Risk Factor: Low

Score: 3


Risk Factor: Medium

Base Score: 5.8

Temporal Score: 4.3

Vector: AV:N/AC:M/Au:N/C:P/I:P/A:N

Temporal Vector: E:U/RL:OF/RC:C


Risk Factor: Medium

Base Score: 6.1

Temporal Score: 5.3

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:fortinet:fortios

Required KB Items: Host/Fortigate/version, Settings/ParanoidReport

Exploit Ease: No known exploits are available

Patch Publication Date: 5/17/2019

Vulnerability Publication Date: 5/17/2019

Reference Information

CVE: CVE-2018-13384

BID: 108454