CVE-2021-47917Public exploitNetwork attack vector

Session hijacking via stored user-field scripts

Published Feb 1, 2026 · Updated Feb 1, 2026

Stored XSS in SimplePHPscripts Simple CMS PHP 2.1 allows remote authenticated users to execute scripts when an administrator views the user list. The newUser and editUser modules store user-controlled field values and render them in the user-list preview without neutralizing script markup. Low-privileged CMS access is required to plant a payload, and an administrator must open the list; execution in that browser context enables session hijacking or application actions.

CVSS severity5.1
Medium
EPSS probability0.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in SimplePHPscripts Simple CMS PHP 2.1 allows remote authenticated users to execute scripts when an administrator views the user list. The newUser and editUser modules store user-controlled field values and render them in the user-list preview without neutralizing script markup. Low-privileged CMS access is required to plant a payload, and an administrator must open the list; execution in that browser context enables session hijacking or application actions.

The record

CVE
CVE-2021-47917
Published
Feb 1, 2026
Updated
Feb 1, 2026
Vendor
SimplePHPscripts
Product
Simple CMS PHP
Classifications
CWE-79, T1185
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 1, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 1, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=2.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

SimplePHPscripts · Simple CMS PHPversion=2.1

Published CVSS scores

5.1VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N
5.4NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1185Browser Session Cookie

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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