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

Published Dec 23, 2025
·
Updated

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 Software

2 affected components
CmSimple CMSimple
CmSimple CMSimple=5.4

Event History

Dec 23, 2025
CVE Published
via MITRE·07:35 PM
Data Sourced
via MITRE·07:35 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·08:15 PM
DescriptionSeverityWeaknessAffected Software
Aug 22, 58235
Event
via NVD·08:56 PM

Frequently Asked Questions

1

What is the severity of CVE-2021-47733?

CVE-2021-47733 is classified as a medium severity vulnerability due to its potential for cross-site scripting attacks.

2

How do I fix CVE-2021-47733?

To fix CVE-2021-47733, ensure that input filtering is properly configured to sanitize HTML and encoded inputs.

3

What type of vulnerability is CVE-2021-47733?

CVE-2021-47733 is a cross-site scripting (XSS) vulnerability.

4

What can attackers do with CVE-2021-47733?

Attackers can execute arbitrary JavaScript in the context of the victim's browser by injecting malicious scripts.

5

Which software versions are affected by CVE-2021-47733?

CVE-2021-47733 affects CMSimple version 5.4.

Contact

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