CVE-2021-47733CWE-79

CMSimple 5.4 Cross-Site Scripting via HTML Unicode Encoding

Medium · published December 23, 2025

CVSS v4.0
5.1
EPSS
0%
Percentile
17.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
5.1 · MEDIUM
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
EPSS
0.00264 · 17.3th percentile
Weakness
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Published
2025-12-23T19:35Z
EPSS history
Timeline
  • 23 DEC 19:35Z
    CMSimple 5.4 Cross-Site Scripting via HTML Unicode Encoding
    cvelistv5