#VU77175 Heap-based buffer overflow in Fortinet, Inc products - CVE-2023-27997

Vulnerability identifier: #VU77175

Vulnerability risk: Critical

CVSSv4.0: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Red]

CVE-ID: CVE-2023-27997

CWE-ID: CWE-122

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
FortiOS
Operating systems & Components / Operating system
FortiOS-6K7K
Operating systems & Components / Operating system
FortiProxy
Hardware solutions / Routers & switches, VoIP, GSM, etc

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 within the SSL-VPN feature. A remote non-authenticated attacker can send specially crafted requests to the SSL-VPN interface, trigger a heap-based buffer overflow and execute arbitrary code on the target system.

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

Note, the vulnerability is being actively exploited in the wild.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

FortiOS: 6.0.0 - 6.0.16, 6.2.0 - 6.2.13, 6.4.0 - 6.4.12, 7.0.0 - 7.0.11, 7.2.0 - 7.2.4

FortiProxy: 1.1.0 - 1.1.6, 1.2.0 - 1.2.13, 2.0.0 - 2.0.12, 7.0.0 - 7.0.9, 7.2.0 - 7.2.3

FortiOS-6K7K: 6.0.10 - 7.0.10

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External links
https://fortiguard.fortinet.com/psirt/FG-IR-23-097
https://www.fortinet.com/blog/psirt-blogs/analysis-of-cve-2023-27997-and-clarifications-on-volt-typhoon-campaign

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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?

Yes. This vulnerability is being exploited in the wild.