CVE-2021-40905

Name: CVE-2021-40905
Creator: NVD / NIST
Published: 2022-03-25T23:15:08.237+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 2.81%

Last modified Jun 17, 2026

CVE-2021-40905 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. The web management console of CheckMK Enterprise Edition (versions 1.5.0 to 2.0.0p9) does not properly sanitise the uploading of ".mkp" files, which are Extension Packages, making remote code execution possible. Successful exploitation requires access to the web management interface, either with valid credentials or with a hijacked session of a user with administrator role. EPSS estimates a 2.81% chance of exploitation in the next 30 days.

Description

The web management console of CheckMK Enterprise Edition (versions 1.5.0 to 2.0.0p9) does not properly sanitise the uploading of ".mkp" files, which are Extension Packages, making remote code execution possible. Successful exploitation requires access to the web management interface, either with valid credentials or with a hijacked session of a user with administrator role. NOTE: the vendor states that this is the intended behavior: admins are supposed to be able to execute code in this manner

Metrics

CVSS 3.1

8.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS Probability

2.81%

84.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Checkmk	Checkmk	2.0.0
Tribe29	Checkmk	>= 1.5.0, < 2.0.0

References

http://checkmk.comProduct
https://github.com/Edgarloyola/CVE-2021-40905Exploit, Third Party Advisory
http://checkmk.comProduct
https://github.com/Edgarloyola/CVE-2021-40905Exploit, Third Party Advisory

Timeline

Published: Mar 25, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-40905?

How severe is CVE-2021-40905?

CVE-2021-40905 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 2.81% probability of exploitation in the next 30 days.

How do I fix CVE-2021-40905?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-40905?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST