Fortinet FortiClient up to 5.2.3 IOCTL Call Fortishield.sys 0x220024/0x220028 access control

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability was found in Fortinet FortiClient up to 5.2.3. It has been rated as problematic. This issue affects an unknown functionality of the file Fortishield.sys of the component IOCTL Call Handler. The manipulation of the argument 0x220024/0x220028 with an unknown input leads to a access control vulnerability. Using CWE to declare the problem leads to CWE-264. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

The Fortishield.sys driver in Fortinet FortiClient before 5.2.4 allows local users to execute arbitrary code with kernel privileges by setting the callback function in a (1) 0x220024 or (2) 0x220028 ioctl call.

The weakness was released 09/03/2015 (Website). The advisory is shared at The identification of this vulnerability is CVE-2015-5736 since 08/04/2015. An attack has to be approached locally. No form of authentication is needed for a successful exploitation. Technical details as well as a public exploit are known. MITRE ATT&CK project uses the attack technique T1068 for this issue.

A public exploit has been developed by sickness and been published 2 years after the advisory. The exploit is available at It is declared as proof-of-concept. The commercial vulnerability scanner Qualys is able to test this issue with plugin 123870 (FortiClient Antivirus Multiple Security Vulnerabilities).

Upgrading to version 5.2.4 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Exploit-DB (41721).






CPE 2.3info

CPE 2.2info


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VulDB Meta Base Score: 5.9
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.9
VulDB Temp Score: 5.3
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Class: Access control
CWE: CWE-264

Local: Yes
Remote: No

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Author: sickness
Download: 🔍

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Threat Intelligenceinfo

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Recommended: Upgrade
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Upgrade: FortiClient 5.2.4


08/04/2015 🔍
09/01/2015 +28 days 🔍
09/01/2015 +0 days 🔍
09/03/2015 +2 days 🔍
09/03/2015 +0 days 🔍
09/04/2015 +1 days 🔍
09/30/2015 +25 days 🔍
03/24/2017 +542 days 🔍
03/24/2017 +0 days 🔍
06/14/2022 +1907 days 🔍



Advisory: 133398
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2015-5736 (🔍)
SecurityTracker: 1033439
Vulnerability Center: 53036 - Fortinet FortiClient before 5.2.4 Local Privilege Escalation Vulnerability in Fortishield.sys Driver, High
SecurityFocus: 76542 - FortiClient CVE-2015-5736 Local Privilege Escalation Vulnerability

scip Labs:


Created: 09/04/2015 10:21 AM
Updated: 06/14/2022 09:20 AM
Changes: 09/04/2015 10:21 AM (55), 10/29/2018 06:04 AM (17), 06/14/2022 09:20 AM (4)
Complete: 🔍
Cache ID: 3:6D1:40


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