#VU55545 Buffer overflow in FortiOS - CVE-2021-24018

Vulnerability identifier: #VU55545

Vulnerability risk: Medium

CVSSv4.0: 5.2 [CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-24018

CWE-ID: CWE-119

Exploitation vector: Local network

Exploit availability: No

Vulnerable software:
FortiOS
Operating systems & Components / Operating system

Vendor: Fortinet, Inc

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error in the firmware verification routine of FortiOS. A remote attacker on the local network can execute arbitrary code via a specifically crafted firmware image.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

FortiOS: 6.4.0 - 6.4.6, 7.0.0

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External links
https://www.fortiguard.com/psirt/FG-IR-21-046

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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 local network (LAN).

Is there known malware, which exploits this vulnerability?

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