#VU18513 Insecure DLL loading in Fortinet FortiClient for Windows - CVE-2019-5589

Vulnerability identifier: #VU18513

Vulnerability risk: Medium

CVSSv4.0: 4.8 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2019-5589

CWE-ID: CWE-427

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Fortinet FortiClient for Windows
Server applications / Other server solutions

Vendor: Fortinet, Inc

Description

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.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Fortinet FortiClient for Windows: 6.0.0 - 6.0.5

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External links
https://fortiguard.com/psirt/FG-IR-19-060

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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.