CVE-2021-4244Network attack vector

Browser script execution via unescaped form fields

Published Dec 12, 2022 · Updated Apr 15, 2025

Reflected XSS in Easy Forms for Mailchimp 6.8.5 and earlier allows remote authenticated users to execute script via crafted form fields. The add_field_to_form.php handler copies field_name, merge_tag, field_type, and list_id POST values into HTML without sanitizing or context-specific escaping. A low-privileged user must submit the request and induce another user to render the reflected response, limiting impact to browser-context data access or content changes.

CVSS severity2.6
Low
EPSS probability0.55%
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 Easy Forms for Mailchimp 6.8.5 and earlier allows remote authenticated users to execute script via crafted form fields. The add_field_to_form.php handler copies field_name, merge_tag, field_type, and list_id POST values into HTML without sanitizing or context-specific escaping. A low-privileged user must submit the request and induce another user to render the reflected response, limiting impact to browser-context data access or content changes.

The record

CVE
CVE-2021-4244
Published
Dec 12, 2022
Updated
Apr 15, 2025
Vendor
YIKES, Inc.
Product
Easy Forms for Mailchimp
Classifications
CWE-79, CWE-707
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 12, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 15, 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=6.8.0
  2. Affected versionversion=6.8.1
  3. Affected versionversion=6.8.2
  4. Affected versionversion=6.8.3
  5. Affected versionversion=6.8.4
  6. Affected versionversion=6.8.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

YIKES, Inc. · Easy Forms for Mailchimpversion=6.8.0; version=6.8.1; version=6.8.2; version=6.8.3; version=6.8.4; version=6.8.5

Published CVSS scores

6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
2.6VulDB CNACVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Cross Site Scripting
CWE-707Improper Neutralization

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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