Vulnerability · Published Dec 23, 2025 · Assigned by VulnCheck
CVE-2021-47733CMSimple 5.4 Cross-Site Scripting via HTML Unicode Encoding
Medium 6.1
In plain English
A medium-severity cross-site scripting in CMSimple from Cmsimple. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 18% of all known vulnerabilities).
Severity (CVSS 3.1)6.1Medium
Exploit odds (30 days)0.3%top 81.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
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.
Affected products (as reported)
Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
References
- ExploitDB-50612 exploit
- CMSimple Official Homepage product
- VulnCheck Advisory: CMSimple 5.4 Cross-Site Scripting via HTML Unicode Encoding third-party-advisory