CVE-2020-12820

Under non-default configuration, a stack-based buffer overflow in FortiOS version 6.0.10 and below, version 5.6.12 and below may allow a remote attacker authenticated to the SSL VPN to crash the FortiClient NAC daemon (fcnacd) and potentially execute arbitrary code via requesting a large FortiClient file name. We are not aware of proof of concept code successfully achieving the latter.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://fortiguard.fortinet.com/psirt/FG-IR-20-083	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:fortinet:fortios::::::::
	cpe:2.3:o:fortinet:fortios::::::::

History

21 Jan 2025, 20:42

Type	Values Removed	Values Added
First Time		Fortinet fortios Fortinet
CPE		cpe:2.3:o:fortinet:fortios::::::::
References	~~() https://fortiguard.fortinet.com/psirt/FG-IR-20-083 -~~	() https://fortiguard.fortinet.com/psirt/FG-IR-20-083 - Vendor Advisory
CWE		CWE-787

19 Dec 2024, 11:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2024-12-19 11:15

Updated : 2025-01-21 20:42

NVD link : CVE-2020-12820

Mitre link : CVE-2020-12820

CVE.ORG link : CVE-2020-12820

JSON object : View

Products Affected

fortinet

fortios

CWE

CWE-121

Stack-based Buffer Overflow

CWE-787

Out-of-bounds Write

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