CVE-2021-47917

Name: CVE-2021-47917
Creator: NVD / NIST
Published: 2026-02-01T13:15:56.073+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.1/10EPSS 0.29%

Last modified Jun 17, 2026

CVE-2021-47917 is a medium-severity vulnerability rated 5.1/10 on the CVSS scale. Simple CMS 2.1 contains a persistent cross-site scripting vulnerability in user input parameters that allows remote attackers to inject malicious script code. Attackers can exploit the newUser and editUser modules to inject persistent scripts that execute on user list preview, potentially leading to session hijacking and application manipulation.. EPSS estimates a 0.29% chance of exploitation in the next 30 days.

Description

Simple CMS 2.1 contains a persistent cross-site scripting vulnerability in user input parameters that allows remote attackers to inject malicious script code. Attackers can exploit the newUser and editUser modules to inject persistent scripts that execute on user list preview, potentially leading to session hijacking and application manipulation.

Metrics

CVSS 3.1

5.4/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

CVSS 4.0

5.1/10

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS Probability

0.29%

20.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Simplephpscripts	Simple Cms Php	2.1

References

https://simplephpscripts.com/simple-cms-phpProduct
https://www.vulncheck.com/advisories/simple-cms-persistent-cross-site-scripting-via-user-input-parametersThird Party Advisory
https://www.vulnerability-lab.com/get_content.php?id=2302Exploit, Third Party Advisory

Timeline

Published: Feb 1, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2021-47917?

How severe is CVE-2021-47917?

CVE-2021-47917 has a CVSS score of 5.1/10 (MEDIUM severity). The EPSS model estimates a 0.29% probability of exploitation in the next 30 days.

How do I fix CVE-2021-47917?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-47917?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST