CVE-2024-5053Network attack vector

Integration request redirection via unchecked API key

Published Sep 1, 2024 · Updated Apr 8, 2026

Improper authorization in Fluent Forms 5.1.18 and earlier allows remote authenticated users to replace the Mailchimp API key. The verifyRequest function accepts Form Manager requests without a sufficient capability check and stores an unvalidated Mailchimp API key. Subscriber-level access is enough to redirect Mailchimp integration requests to an attacker-controlled server, exposing transmitted data.

CVSS severity4.2
Medium
EPSS probability0.40%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authorization in Fluent Forms 5.1.18 and earlier allows remote authenticated users to replace the Mailchimp API key. The verifyRequest function accepts Form Manager requests without a sufficient capability check and stores an unvalidated Mailchimp API key. Subscriber-level access is enough to redirect Mailchimp integration requests to an attacker-controlled server, exposing transmitted data.

The record

CVE
CVE-2024-5053
Published
Sep 1, 2024
Updated
Apr 8, 2026
Vendor
Mahmudul Hasan Arif
Product
Fluent Forms
Classifications
CWE-862, CWE-285, T1565.002
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 1, 2024CVE publishedPublication date reported by the CVE source.
  2. Apr 8, 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 <=5.1.18

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Mahmudul Hasan Arif · Fluent Formsversion=0 <=5.1.18

Published CVSS scores

4.2WordfenceCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N
4.3NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/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-862Missing Authorization
CWE-285Improper Authorization
T1565.002Transmitted Data Manipulation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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