Fortinet FortiOS Web Interface Cookie Parser RCE (EGREGIOUSBLUNDER)

critical Nessus Plugin ID 93196
New! Plugin Severity Now Using CVSS v3

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Synopsis

A web-based management console running on the remote host is affected by a remote code execution vulnerability.

Description

The Fortinet FortiOS management console running on the remote host is affected by a remote code execution vulnerability, known as EGREGIOUSBLUNDER, in its web interface due to improper validation when parsing cookies. An unauthenticated, remote attacker can exploit this, via a specially crafted HTTP request, to cause a buffer overflow condition, resulting in a denial of service condition or the execution of arbitrary code.

EGREGIOUSBLUNDER is one of multiple Equation Group vulnerabilities and exploits disclosed on 2016/08/14 by a group known as the Shadow Brokers.

Note that this plugin attempts to kill the httpsd process, which appears to restart after termination. Additionally, this plugin requires report paranoia as it relies on a missing server response to indicate a vulnerable status, which may or may not be reliable.

Solution

Upgrade to Fortinet FortiOS 4.1.11 / 4.2.13 / 4.3.9 / 5.0 or later.

See Also

https://fortiguard.com/psirt/FG-IR-16-023

http://www.nessus.org/u?4c7e0cf3

Plugin Details

Severity: Critical

ID: 93196

File Name: fortios_cookie_parsing_bof.nasl

Version: 1.7

Type: remote

Family: CGI abuses

Published: 8/29/2016

Updated: 11/15/2018

Dependencies: fortigate_detect.nasl

Configuration: Enable paranoid mode

Risk Information

VPR

Risk Factor: High

Score: 8.4

CVSS v2

Risk Factor: Critical

Base Score: 10

Temporal Score: 8.3

Vector: AV:N/AC:L/Au:N/C:C/I:C/A:C

Temporal Vector: E:F/RL:OF/RC:ND

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 9.1

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

Temporal Vector: E:F/RL:O/RC:X

Vulnerability Information

CPE: cpe:/o:fortinet:fortios

Required KB Items: www/fortios_ui, Settings/ParanoidReport

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 8/17/2016

Vulnerability Publication Date: 8/14/2016

Reference Information

CVE: CVE-2016-6909

BID: 92523

EDB-ID: 40276