Fortinet FortiOS <= 6.2.5 / 6.4 <= 6.4.2 Traffic Bypass (FG-IR-20-172)

medium Nessus Plugin ID 147661
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VPR Score: 3.6


The remote host is affected by a traffic bypass vulnerability.


The remote host is running a version of FortiOS prior or equal to 6.2.5, or 6.4 prior to 6.4.3. It is, therefore, affected by a traffic bypass vulnerability. When traffic other than HTTP/S (eg: SSH traffic, etc...) traverses the FortiGate in version below 6.2.5 and below 6.4.2 on port 80/443, it is not redirected to the transparent proxy policy for processing, as it doesn't have a valid HTTP header.


Upgrade to Fortinet FortiOS version to 6.4.3 or later.

See Also

Plugin Details

Severity: Medium

ID: 147661

File Name: fortios_FG-IR-20-172.nasl

Version: 1.8

Type: local

Family: Firewalls

Published: 3/11/2021

Updated: 4/29/2021

Dependencies: fortinet_version.nbin

Risk Information

Risk Factor: Medium

VPR Score: 3.6

CVSS Score Source: CVE-2020-15938

CVSS v2.0

Base Score: 4.3

Temporal Score: 3.2

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

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

CVSS v3.0

Base Score: 7.5

Temporal Score: 6.5

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

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

Vulnerability Information

CPE: cpe:/o:fortinet:fortios

Required KB Items: Host/Fortigate/version

Exploit Ease: No known exploits are available

Patch Publication Date: 1/21/2021

Vulnerability Publication Date: 1/21/2021

Reference Information

CVE: CVE-2020-15938

IAVA: 2021-A-0120