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Fencer Intel
critical 9.8

CVE-2020-28871 in the critical feed json

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 i…

published 5y ago modified 4mo ago also EUVD-2020-21262

cvss
9.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
85.9%
EPSS 85.9% chance of exploitation in 30 days, percentile 99.7%
public exploits
1
Metasploit, plus a Nuclei check

Summary

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.

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Timeline

  1. First public exploit (Metasploit exploit/multi/http/monitorr_webshell_rce_cve_2020_28871)
  2. Published

Exploit prediction

85.90% chance of exploitation in the next 30 days, higher than 99.7% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • Metasploit exploit/multi/http/monitorr_webshell_rce_cve_2020_28871 Monitorr unauthenticated Remote Code Execution (RCE) metasploit exploit, excellent rank, 2020-11-16
  • Nuclei template Monitorr 1.7.6m - Unauthenticated Remote Code Execution nuclei detection template
  • lyhinslab.org https://lyhinslab.org/index.php/2020/09/12/how-the-white-box-hacking-works-authorization-bypass-and-remote-code-execution-in-monitorr-1-7-6/ referenced PoC, tagged "exploit" by a source, unverified
  • exploit-db.com https://www.exploit-db.com/exploits/48980 referenced PoC, tagged "exploit" by a source, unverified
  • packetstormsecurity.com http://packetstormsecurity.com/files/163263/Monitorr-1.7.6m-Bypass-Information-Disclosure-Shell-Upload.html referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 7.5 AV:N/AC:L/Au:N/C:P/I:P/A:P

Classification

Weakness
  • CWE-434 Unrestricted Upload of File with Dangerous Type

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.