CVE-2021-47733 MEDIUM

CVE-2021-47733: CMSimple 5.4 Cross-Site Scripting via HTML Unicode Encoding

Vendor Cmsimple
Product CMSimple
Weakness CWE-79 · XSS
Published December 23, 2025
Last update April 7, 2026

CVSS base score

5.1/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

December 23, 2025 CVE published
April 7, 2026 Record updated