CVE-2024-8850Network attack vector

Script execution via unescaped email placeholder

Published Sep 19, 2024 · Updated Sep 25, 2024

Reflected XSS in MC4WP: Mailchimp for WordPress 4.9.9 through 4.9.16 allows remote attackers to inject scripts via email. The form renderer substitutes the email request parameter into a configured {email} field placeholder without sufficient input sanitization or output escaping. The affected form must use that placeholder, and a victim must follow a crafted link before the script runs in the site's browser context.

CVSS severity6.1
Medium
EPSS probability0.48%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected XSS in MC4WP: Mailchimp for WordPress 4.9.9 through 4.9.16 allows remote attackers to inject scripts via email. The form renderer substitutes the email request parameter into a configured {email} field placeholder without sufficient input sanitization or output escaping. The affected form must use that placeholder, and a victim must follow a crafted link before the script runs in the site's browser context.

The record

CVE
CVE-2024-8850
Published
Sep 19, 2024
Updated
Sep 25, 2024
Vendor
ibericode
Product
MC4WP: Mailchimp for WordPress
Classifications
CWE-79, T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 19, 2024CVE publishedPublication date reported by the CVE source.
  2. Sep 25, 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=4.9.9 <=4.9.16

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ibericode · MC4WP: Mailchimp for WordPressversion=4.9.9 <=4.9.16

Published CVSS scores

6.1WordfenceCVSS:3.1/AV:N/AC:L/PR:N/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1189Drive-by Compromise

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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