Authenticated denial of service in FortiOS SSL VPN

Published: 2025-04-09

Risk	Medium
Patch available	YES
Number of vulnerabilities	2
CVE-ID	CVE-2023-42785 CVE-2023-42786
CWE-ID	CWE-476
Exploitation vector	Network
Public exploit	N/A
Vulnerable software	FortiOS Operating systems & Components / Operating system
Vendor	Fortinet, Inc

Security Bulletin

This security bulletin contains information about 2 vulnerabilities.

1) NULL pointer dereference

EUVDB-ID: #VU107319

Risk: Medium

CVSSv4.0: 4.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2023-42785

CWE-ID: CWE-476 - NULL Pointer Dereference

Exploit availability: No

Description

The vulnerability allows a remote user to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error in SSL VPN service. A remote user can send a specially crafted HTTP request and crash the system.

Mitigation

Install update from vendor's website.

Vulnerable software versions

FortiOS: 6.0.0 - 7.6.2

CPE2.3

External links

https://fortiguard.fortinet.com/psirt/FG-IR-23-293

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

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

2) NULL pointer dereference

EUVDB-ID: #VU107320