Arbitrary file upload in Checkmk
CVE-2021-40905
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.
Vulnerability class: Unrestricted File Upload
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.030 (87.3th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 87th percentile — 87.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.030 · newest: 0.030 · change: 0.000
Affected products
- Checkmk — versions 2.0.0
- Tribe29 Checkmk
Weakness classification (CWE)
Public proof-of-concept exploits
References
- af854a3a-2127-422b-91ae-364da2661108 (Product)
- github.com/Edgarloyola/CVE-2021-40905 (Exploit, Third Party Advisory)
- docs.checkmk.com/latest/en/mkps.html
Frequently asked questions
- What is CVE-2021-40905?
- CVE-2021-40905 is a high-severity vulnerability in Checkmk, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 8.8/10. Published 2022-03-25.
- How severe is CVE-2021-40905?
- High severity. CVSS v3 base score is 8.8 out of 10.
- Is CVE-2021-40905 known to be exploited?
- 10 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.