CVE-2020-28871
CriticalPublic exploitRemote code execution in Monitorr v1.7.6m in upload.php allows an unauthorized person to execute arbitrary code on the server-side via an insecure file upload.
Published Feb 9, 2021 · Updated Jul 8, 2026
Key Facts
Patch immediately- CVE-2020-28871 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting Monitorr.
- It is not listed in any known-exploited vulnerabilities catalog. Public exploit code is available.
- EPSS estimates a 86% probability of exploitation in the next 30 days.
- No fixed version is listed yet; check the vendor advisory for mitigations.
- Brandefense priority: patch immediately, because it is very likely to be exploited soon.
CVSS v3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
86%
Higher than 99.7% of all scored CVEs
Exploited in the wild
No known
Not in a known-exploited catalog
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2020-28871 brief as a PDF
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Description
Remote code execution in Monitorr v1.7.6m in upload.php allows an unauthorized person to execute arbitrary code on the server-side via an insecure file upload.
Affected Products
1 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| MonitorrMonitorr | 1.7.6m | n/a |
Timeline
Publicly disclosed
Feb 9, 2021
Last updated
Jul 8, 2026
Weakness Type
- CWE-434 Unrestricted Upload of File with Dangerous Type
References
- exploithttp://packetstormsecurity.com/files/163263/Monitorr-1.7.6m-Bypass-Information-Disclosure-Shell-Upload.html
- exploitMSF monitorr_webshell_rce_cve_2020_28871.rb
- exploithttps://lyhinslab.org/index.php/2020/09/12/how-the-white-box-hacking-works-authorization-bypass-and-remote-code-execution-in-monitorr-1-7-6/
- exploithttps://www.exploit-db.com/exploits/48980
- otherhttp://packetstormsecurity.com/files/170974/Monitorr-1.7.6-Shell-Upload.html
FAQ
Common Questions.
Remote code execution in Monitorr v1.7.6m in upload.php allows an unauthorized person to execute arbitrary code on the server-side via an insecure file upload.
Affected: Monitorr versions 1.7.6m. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
No fixed version is listed yet; check the vendor advisory for mitigations.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.
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