Insecure DLL loading in Fortinet FortiClient

Published: 2019-05-16 | Updated: 2019-05-16
Severity Medium
Patch available YES
Number of vulnerabilities 1
CVE ID CVE-2019-5589
Exploitation vector Network
Public exploit N/A
Vulnerable software Fortinet FortiClient Subscribe
Vendor Fortinet, Inc

Security Advisory

This security advisory describes one medium risk vulnerability.

1) Insecure DLL loading

Severity: Medium

CVSSv3: 6.5 [CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C] [PCI]

CVE-ID: CVE-2019-5589

CWE-ID: CWE-427 - Uncontrolled Search Path Element


The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to the application loads DLL libraries in an insecure manner during installation, when FortiClientOnlineInstaller.exe is executed. A remote attacker can place a specially crafted .dll file on a remote SMB fileshare, trick the victim into executing the FortiClientOnlineInstaller.exe file from the share and execute arbitrary code on victim's system.


Install updates from vendor's website.

Vulnerable software versions

Fortinet FortiClient: 6.0.0, 6.0.1, 6.0.2, 6.0.3, 6.0.4, 6.0.5

CPE External links

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.