CVE-2021-47753

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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.exploit-db.com/exploits/50610	Exploit Third Party Advisory
https://www.phpkf.com/	Product
https://www.phpkf.com/indirme.php	Product
https://www.exploit-db.com/exploits/50610	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:phpkf:cms:3.00:beta_y6:*:*:*:*:*:*

History

No history.

Information

Published : 2026-01-15 16:16

Updated : 2026-01-23 18:31

NVD link : CVE-2021-47753

Mitre link : CVE-2021-47753

CVE.ORG link : CVE-2021-47753

JSON object : View

Products Affected

phpkf

cms

CWE

CWE-434

Unrestricted Upload of File with Dangerous Type

{"id": "CVE-2021-47753", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 9.8, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 3.9}], "cvssMetricV40": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 9.3, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "valueDensity": "NOT_DEFINED", "vectorString": "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "published": "2026-01-15T16:16:06.003", "references": [{"url": "https://www.exploit-db.com/exploits/50610", "tags": ["Exploit", "Third Party Advisory"], "source": "disclosure@vulncheck.com"}, {"url": "https://www.phpkf.com/", "tags": ["Product"], "source": "disclosure@vulncheck.com"}, {"url": "https://www.phpkf.com/indirme.php", "tags": ["Product"], "source": "disclosure@vulncheck.com"}, {"url": "https://www.exploit-db.com/exploits/50610", "tags": ["Exploit", "Third Party Advisory"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "description": [{"lang": "en", "value": "CWE-434"}]}], "descriptions": [{"lang": "en", "value": "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."}], "lastModified": "2026-01-23T18:31:05.153", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:phpkf:cms:3.00:beta_y6:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0C662776-4E67-437B-A740-52624381AE63"}], "operator": "OR"}]}], "sourceIdentifier": "disclosure@vulncheck.com"}