CVE-2026-15052Network attack vector

Stored XSS via unescaped form field values

Published Aug 1, 2026 · Updated Aug 1, 2026

Stored XSS in PluginOps MailChimp Subscribe Form 4.3.3 and earlier allows remote attackers to inject scripts through form field values. Unauthenticated form-submission handlers persist field values without neutralizing HTML, and later rendering paths insert those values into pages without output escaping. Any visitor who can submit an exposed form can plant script that runs in the browser of each user who views the affected page.

CVSS severity7.2
High
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 PluginOps MailChimp Subscribe Form 4.3.3 and earlier allows remote attackers to inject scripts through form field values. Unauthenticated form-submission handlers persist field values without neutralizing HTML, and later rendering paths insert those values into pages without output escaping. Any visitor who can submit an exposed form can plant script that runs in the browser of each user who views the affected page.

The record

CVE
CVE-2026-15052
Published
Aug 1, 2026
Updated
Aug 1, 2026
Vendor
PluginOps
Product
MailChimp Subscribe Form, Optin Builder, PopUp Builder, Form Builder
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 1, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 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=0 <=4.3.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

PluginOps · MailChimp Subscribe Form, Optin Builder, PopUp Builder, Form Builderversion=0 <=4.3.3

Published CVSS scores

7.2WordfenceCVSS:3.1/AV:N/AC:L/PR:N/UI:N/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007JavaScript/JScript

Public exploit references

No public exploit references are available in this record.

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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