CVE-2025-3581Public exploitNetwork attack vector

Stored XSS via unescaped widget introduction

Published Jun 9, 2025 · Updated Jun 10, 2025

Stored XSS in The Newsletter Plugin's Newsletter before 8.8.5 allows remote authenticated users to execute script via crafted widget options. The classic Newsletter widget stores its Introduction field without validation or output escaping, then renders that value on every front-end page. Administrator privileges are required, and the flaw remains reachable when unfiltered_html is disabled; execution occurs when a visitor loads a page containing the widget.

CVSS severity4.8
Medium
EPSS probability0.26%
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 The Newsletter Plugin's Newsletter before 8.8.5 allows remote authenticated users to execute script via crafted widget options. The classic Newsletter widget stores its Introduction field without validation or output escaping, then renders that value on every front-end page. Administrator privileges are required, and the flaw remains reachable when unfiltered_html is disabled; execution occurs when a visitor loads a page containing the widget.

The record

CVE
CVE-2025-3581
Published
Jun 9, 2025
Updated
Jun 10, 2025
Vendor
The Newsletter Plugin
Product
Newsletter
Classifications
CWE-79, T1203
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Jun 9, 2025CVE publishedPublication date reported by the CVE source.
  2. Jun 10, 2025Record 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=0 <8.8.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

The Newsletter Plugin · Newsletterversion=0 <8.8.5

Published CVSS scores

4.8CISA-ADPCVSS: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.

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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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

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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