CVE-2021-47753 (GCVE-0-2021-47753)

Vulnerability from cvelistv5 – Published: 2026-01-15 15:52 – Updated: 2026-04-07 14:05
VLAI
Title
phpKF CMS 3.00 Beta y6 - Remote Code Execution (RCE) (Unauthenticated)
Summary
phpKF CMS 3.00 Beta y6 contains an unauthenticated file upload vulnerability that allows remote attackers to execute arbitrary code by bypassing file extension checks. Attackers can upload a PHP file disguised as a PNG, rename it, and execute system commands through a crafted web shell parameter.
Severity
9.3 (Critical)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
  • CWE-434 - Unrestricted Upload of File with Dangerous Type
Assigner
References
Impacted products
Vendor Product Version
Phpkf phpKF CMS Affected: 3.00
Create a notification for this product.
Date Public
2021-12-20 00:00
Credits
Halit AKAYDIN (hLtAkydn)
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.