CVE-2020-12820: Buffer Overflow

Published Dec 19, 2024
·
Updated

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.

Affected Software

4 affected components
Fortinet FortiOS<6.0.10
Fortinet FortiOS<5.6.12
Fortinet FortiOS<5.6.13
Fortinet FortiOS>=6.0.0<6.0.11

Remediation

Information

Please upgrade to FortiOS versions 5.6.13 or above. Please upgrade to FortiOS versions 6.0.11 or above. FortiOS versions 6.2.0 and above are not impacted. FortiOS versions 6.4.0 and above are not impacted. Workaround: Please ensure that Fortiheartbeat and Endpoint-Compliance are not both enabled on the same interface. FortiHeartbeat and Endpoint-Compliance can be disabled on a particular interface by following the below CLI commands: config system interface edit interface set endpoint-compliance disable (<-- Disabled by default) set fortiheartbeat disable next end

Event History

Dec 19, 2024
CVE Published
via MITRE·10:57 AM
Data Sourced
via MITRE·10:57 AM
RemedyDescriptionSeverityWeakness
Data Sourced
via NVD·11:15 AM
DescriptionSeverityWeakness

Frequently Asked Questions

1

What is the severity of CVE-2020-12820?

CVE-2020-12820 is classified as a high-severity vulnerability due to its potential for remote code execution.

2

How do I fix CVE-2020-12820?

To fix CVE-2020-12820, upgrade FortiOS to version 6.0.11 or 5.6.13 or later.

3

What can an attacker do with CVE-2020-12820?

An authenticated attacker can exploit CVE-2020-12820 to crash the FortiClient NAC daemon and could potentially execute arbitrary code.

4

Which versions of FortiOS are affected by CVE-2020-12820?

CVE-2020-12820 affects FortiOS versions 6.0.10 and below, as well as 5.6.12 and below.

5

Is CVE-2020-12820 related to SSL VPN access?

Yes, CVE-2020-12820 can be exploited by attackers authenticated to the SSL VPN.

Company

Resources

Contact

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info@secalerts.co
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