CVE-2020-20951Public exploitNetwork attack vector

Authenticated code execution via duplicate PHP upload

Published May 18, 2021 · Updated Aug 4, 2024

Unrestricted file upload in Pluck CMS 4.7.10-dev2 allows remote authenticated users to execute PHP code through the admin interface. The upload handler renames the first shell.php submission to shell.php.txt but leaves a second shell.php submission executable. Access to the management interface and PHP 5.2 are required, after which opening the uploaded file runs attacker-controlled server code.

CVSS severity9.8
Critical
EPSS probability4.03%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Unrestricted file upload in Pluck CMS 4.7.10-dev2 allows remote authenticated users to execute PHP code through the admin interface. The upload handler renames the first shell.php submission to shell.php.txt but leaves a second shell.php submission executable. Access to the management interface and PHP 5.2 are required, after which opening the uploaded file runs attacker-controlled server code.

The record

CVE
CVE-2020-20951
Published
May 18, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-77, T1505.003
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 18, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-77Improper Neutralization of Special Elements used in a Command ('Command Injection')
T1505.003Server Software Component: Web Shell

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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