CVE-2021-47733

CMSimple 5.4 contains a cross-site scripting vulnerability that allows attackers to bypass input filtering by using HTML to Unicode encoding. Attackers can inject malicious scripts by encoding payloads like ')-alert(1)// and execute arbitrary JavaScript when victims interact with delete buttons.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://www.cmsimple.org/en/	Product
https://www.exploit-db.com/exploits/50612	Exploit
https://www.vulncheck.com/advisories/cmsimple-cross-site-scripting-via-html-unicode-encoding	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:cmsimple:cmsimple:5.4:*:*:*:*:*:*:*

History

31 Dec 2025, 21:43

Type	Values Removed	Values Added
CPE		cpe:2.3:a:cmsimple:cmsimple:5.4:::::::*
First Time		Cmsimple Cmsimple cmsimple
References	~~() https://www.cmsimple.org/en/ -~~	() https://www.cmsimple.org/en/ - Product
References	~~() https://www.exploit-db.com/exploits/50612 -~~	() https://www.exploit-db.com/exploits/50612 - Exploit
References	~~() https://www.vulncheck.com/advisories/cmsimple-cross-site-scripting-via-html-unicode-encoding -~~	() https://www.vulncheck.com/advisories/cmsimple-cross-site-scripting-via-html-unicode-encoding - Third Party Advisory

23 Dec 2025, 20:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-12-23 20:15

Updated : 2025-12-31 21:43

NVD link : CVE-2021-47733

Mitre link : CVE-2021-47733

CVE.ORG link : CVE-2021-47733

JSON object : View

Products Affected

cmsimple

cmsimple

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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