CVE-2021-47753 | phpKF CMS 3.00 Beta y6 contains an unauthenticated file uplo… | CVSS 9.8 CRITICAL

Description

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.

Metadata

CVE ID: CVE-2021-47753
State: PUBLISHED
Assigner: VulnCheck
Reserved: 2026-01-10 13:48 UTC
Published: 2026-01-15 15:52 UTC
Last updated: 2026-04-07 14:05 UTC
Primary CWE: CWE-434
Unrestricted Upload of File with Dangerous Type
Vendor / Product: Phpkf / phpKF CMS
Sources: cve.org · NVD

Severity & Metrics

9.8 CRITICAL CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

SSVC — CISA Coordinator

Exploitation: PoC
Automatable: yes
Tech. Impact: total

Affected products (1)

Vendor	Product	Platform	Versions
Phpkf	phpKF CMS	—	3.00

Weakness (CWE)

CWE	Source	Description
CWE-434	cna	Unrestricted Upload of File with Dangerous Type

CVSS scores (2)

Score	Severity	Version	Source	Vector
9.8	CRITICAL	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.3	CRITICAL	4.0	cna	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

References (3)

ExploitDB-50610 https://www.exploit-db.com/exploits/50610
Official Vendor Homepage https://www.phpkf.com/
Software Download Page https://www.phpkf.com/indirme.php