CVE-2021-24533Public exploitNetwork attack vector

Administrator-stored script execution via unescaped settings

Published Aug 23, 2021 · Updated Aug 3, 2024

Stored XSS in WebFactory Ltd Maintenance before 4.03 allows remote authenticated users with administrator access to run script in visitors' browsers. The settings handler stores controls_bg_color and custom_css values without sanitization, and the maintenance-page renderer emits them without escaping. Administrator access and maintenance mode are required; visiting the homepage then executes the stored payload in the visitor's browser.

CVSS severity4.8
Medium
EPSS probability0.62%
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 WebFactory Ltd Maintenance before 4.03 allows remote authenticated users with administrator access to run script in visitors' browsers. The settings handler stores controls_bg_color and custom_css values without sanitization, and the maintenance-page renderer emits them without escaping. Administrator access and maintenance mode are required; visiting the homepage then executes the stored payload in the visitor's browser.

The record

CVE
CVE-2021-24533
Published
Aug 23, 2021
Updated
Aug 3, 2024
Vendor
WebFactory Ltd
Product
Maintenance
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Aug 23, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record 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=4.03 <4.03

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

WebFactory Ltd · Maintenanceversion=4.03 <4.03

Published CVSS scores

3.5NIST NVDAV:N/AC:M/Au:S/C:N/I:P/A:N
4.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007Command and Scripting Interpreter: JavaScript

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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