Medium severity · published Apr 16, 2026
CVE-2026-4160
Fluent Forms – Customizable Contact Forms, Survey, Quiz, & Conversational Form Builder <= 6.1.21 - Insecure Direct Object Reference in Stripe SCA Confirmation to Unauthenticated Payment Status Modification
5.3
CVSS
0.3%
EPSS
No
On KEV
Description
The Fluent Forms – Customizable Contact Forms, Survey, Quiz, & Conversational Form Builder plugin for WordPress is vulnerable to Insecure Direct Object Reference via the 'submission_id' parameter in versions up to, and including, 6.1.21. This is due to missing authorization and ownership validation on a user controlled key in the Stripe SCA confirmation AJAX endpoint. This makes it possible for unauthenticated attackers to modify payment status of targeted pending submissions (for example, setting the status to "failed").
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 23% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FF
Affected product
FF
Fluent Forms – Customizable Contact Forms, Survey, Quiz, & Conversational Form Builder
techjewel
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-4160
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-4160
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/changeset/3496638/fluentform
www.wordfence.com
https://www.wordfence.com/threat-intel/vulnerabilities/id/154fc656-3a33-4783-a941-10bb848244b3?source=cve
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