CVE-2021-43204: Medium severity fortinet forticlient ssl vpn vulnerability

Published Dec 9, 2021
·
Updated

A improper control of a resource through its lifetime in Fortinet FortiClientWindows version 6.4.1 and 6.4.0, version 6.2.9 and below, version 6.0.10 and below allows attacker to cause a complete denial of service of its components via changes of directory access permissions.

Affected Software

36 affected components
Fortinet FortiClient Windows>=5.0.0<=5.0.11
Fortinet FortiClient Windows>=5.4.0<=5.4.5
Fortinet FortiClient Windows>=5.6.0<=5.6.6
Fortinet FortiClient Windows>=6.0.0<=6.0.10
Fortinet FortiClient Windows>=6.2.0<=6.2.9
Fortinet FortiClient Windows=4.0.1
Fortinet FortiClient Windows=4.0.2
Fortinet FortiClient Windows=4.0.3
Fortinet FortiClient Windows=4.0.4
Fortinet FortiClient Windows=4.1.0
Fortinet FortiClient Windows=4.1.1
Fortinet FortiClient Windows=4.1.2
Fortinet FortiClient Windows=4.1.3
Fortinet FortiClient Windows=4.2.0
Fortinet FortiClient Windows=4.2.1
Fortinet FortiClient Windows=4.2.2
Fortinet FortiClient Windows=4.2.3
Fortinet FortiClient Windows=4.2.4
Fortinet FortiClient Windows=4.2.5
Fortinet FortiClient Windows=4.2.6
Fortinet FortiClient Windows=4.2.7
Fortinet FortiClient Windows=4.3.0
Fortinet FortiClient Windows=4.3.1
Fortinet FortiClient Windows=4.3.2
Fortinet FortiClient Windows=4.3.3
Fortinet FortiClient Windows=4.3.4
Fortinet FortiClient Windows=4.3.5
Fortinet FortiClient Windows=5.2.0
Fortinet FortiClient Windows=5.2.1
Fortinet FortiClient Windows=5.2.2
Fortinet FortiClient Windows=5.2.3
Fortinet FortiClient Windows=5.2.4
Fortinet FortiClient Windows=5.2.5
Fortinet FortiClient Windows=5.2.6
Fortinet FortiClient Windows=6.4.0
Fortinet FortiClient Windows=6.4.1

Remediation

Patch Available

https://fortiguard.com/advisory/FG-IR-21-167

Event History

Dec 9, 2021
CVE Published
via MITRE·09:04 AM
Data Sourced
via MITRE·09:04 AM
DescriptionSeverityWeakness
Data Sourced
via NVD·09:15 AM
RemedyDescriptionSeverityAffected Software
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Frequently Asked Questions

1

What is CVE-2021-43204?

CVE-2021-43204 is a vulnerability that allows an attacker to cause a complete denial of service in Fortinet FortiClientWindows.

2

Which versions of Fortinet FortiClientWindows are affected by CVE-2021-43204?

Fortinet FortiClientWindows versions 6.4.1, 6.4.0, 6.2.9 and below, 6.0.10 and below are affected by CVE-2021-43204.

3

How severe is the vulnerability CVE-2021-43204?

CVE-2021-43204 has a severity rating of 4.4, which is considered medium.

4

How can I fix CVE-2021-43204?

To fix CVE-2021-43204, update your Fortinet FortiClientWindows to a version that is not affected.

5

Where can I find more information about CVE-2021-43204?

You can find more information about CVE-2021-43204 in the advisory published by FortiGuard: https://fortiguard.com/advisory/FG-IR-21-167

Company

Resources

Contact

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