CVE-2023-23995Public exploitNetwork attack vector

Stored XSS via unescaped custom-directory setting

Published Apr 25, 2023 · Updated Apr 28, 2026

Stored XSS in TinyMCE Custom Styles 1.1.2 and earlier allows remote authenticated users to execute script in an administrator's browser. The tcs_cuslink settings field writes unsanitized POST data to wp_options, then inserts it into HTML attributes without escaping. Administrator access is required to store the payload, and script execution occurs when another user opens the plugin settings page.

CVSS severity4.8
Medium
EPSS probability0.39%
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 TinyMCE Custom Styles 1.1.2 and earlier allows remote authenticated users to execute script in an administrator's browser. The tcs_cuslink settings field writes unsanitized POST data to wp_options, then inserts it into HTML attributes without escaping. Administrator access is required to store the payload, and script execution occurs when another user opens the plugin settings page.

The record

CVE
CVE-2023-23995
Published
Apr 25, 2023
Updated
Apr 28, 2026
Vendor
Tim Reeves & David Stöckl
Product
TinyMCE Custom Styles
Classifications
CWE-79, CAPEC-592, T1059.007
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Apr 25, 2023CVE publishedPublication date reported by the CVE source.
  2. Apr 28, 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=n/a <=1.1.2 changes=[{"at":"1.1.3","status":"unaffected"}]

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Tim Reeves & David Stöckl · TinyMCE Custom Stylesversion=n/a <=1.1.2 changes=[{"at":"1.1.3","status":"unaffected"}]

Published CVSS scores

4.8NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
5.9PatchstackCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:L

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')
CAPEC-592Stored XSS
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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