Fortinet FortiOS Heap-based Buffer Overflow (FG-IR-21-115)

high Nessus Plugin ID 156550


The remote host is affected by a heap-based buffer overflow vulnerability.


The remote host is running a version of FortiOS prior to 6.0.13, 6.2.x prior or equal to 6.2.9, 6.4.x prior or equal to 6.4.6, 7.0.x prior or equal to 7.0.1, FortiOS-6K7 prior to 6.0.10, 6.2.x prior or equal to 6.2.7, 6.4.x prior or equal to 6.4.2. It is, therefore, affected by a heap-based buffer overflow vulnerability in the firmware signature verification function of FortiOS may allow an attacker to execute arbitrary code via specially crafted installation images.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.


See vendor advisory.

See Also

Plugin Details

Severity: High

ID: 156550

File Name: fortios_FG-IR-21-115.nasl

Version: 1.5

Type: local

Family: Firewalls

Published: 1/7/2022

Updated: 10/17/2022

Supported Sensors: Nessus

Risk Information


Risk Factor: Medium

Score: 5.9


Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5

Vector: CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:P

CVSS Score Source: CVE-2021-36173


Risk Factor: High

Base Score: 8.8

Temporal Score: 7.7

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

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:fortinet:fortios

Required KB Items: Host/Fortigate/model, Host/Fortigate/version

Exploit Ease: No known exploits are available

Patch Publication Date: 12/7/2021

Vulnerability Publication Date: 12/7/2021

Reference Information

CVE: CVE-2021-36173

IAVA: 2021-A-0574-S