The Formidable Forms plugin for WordPress is vulnerable to PHP Object Injection in versions up to, and including, 6.1.2 via deserialization of untrusted input from form submissions. This allows unauthenticated attackers to inject a PHP Object. No POP chain is present in the vulnerable plugin. If a POP chain is present via an additional plugin or theme installed on the target system, it could allow the attacker to delete arbitrary files, retrieve sensitive data, or execute code.
CVE-2023-1405 is a critical severity with CVSS 9.8 Vulnerability issue affecting the Plugin Formidable Forms – WordPress Form Builder for Contact Forms, Calculators, Quizzes & More. It affects Versions up to 6.1.2 and is fixed in 6.2.
Use the related hub and response guides to connect this CVE-2023-1405 report with patch validation, scanner checks, and site hardening work.
Open the grouped hub for related CVEs, affected ranges, severity mix, and patch coverage.
Check access, XML-RPC exposure, backup readiness, and monitoring after patching.
Use containment, evidence capture, remediation, and validation steps when exploit risk is high.
CVE-2023-1405 is tracked for the Plugin Formidable Forms – WordPress Form Builder for Contact Forms, Calculators, Quizzes & More as critical severity with CVSS 9.8. The affected range is Versions up to 6.1.2. Update Formidable Forms – WordPress Form Builder for Contact Forms, Calculators, Quizzes & More to 6.2 or newer where that version is compatible with the site.
Search engines and operators need more than a title. This page exposes the identifier, affected range, patch evidence, and source coverage that make the vulnerability actionable.
This report has a CVE identifier, which makes it suitable for focused search and vulnerability triage workflows.
Affected version data gives operators a concrete comparison point against installed WordPress software.
A fixed version is present, so the page can answer update and remediation intent directly.
External references are available for source validation, advisory review, and incident notes.
Use these checks when converting this record into a patch ticket, incident note, or risk acceptance decision.
Inventory the installed Plugin package and compare its version with Versions up to 6.1.2.
Confirm Formidable Forms – WordPress Form Builder for Contact Forms, Calculators, Quizzes & More is updated to 6.2 or newer.
Review references and CVSS vector details for exploitability, authentication requirements, and exposure path.
After patching, re-run vulnerability monitoring and keep the related plugin or theme hub under review for follow-up CVEs.
| Software Type | Plugin |
|---|---|
| Software Slug |
formidable
View on wordpress.org
|
| CVE | CVE-2023-1405 |
| Patched Versions |
6.2
|
| Affected Versions |
Versions up to 6.1.2
|
These internal links group the same WordPress plugin by CVE, issue type, severity, and patch status so operators and search engines can connect the full vulnerability cluster.
Formidable Form Builder <= 4.02 - PHP Object Injection
Formidable Form Builder <= 4.09.04 - Unauthenticated Stored Cross-Site Scripting
Formidable Form Builder <= 1.07.11 - SQL Injection
Formidable Form Builder < 2.05.03 - Unauthenticated Stored Cross-Site Scripting
Formidable Forms <= 6.28 - Missing Authorization to Unauthenticated Payment Integrity Bypass via PaymentIntent Reuse
Formidable Form Builder <= 5.5.6 - Cross-Site Request Forgery
Formidable Forms <= 6.7 - HTML Injection
Formidable Forms <= 6.3 - Authenticated (Subscriber+) Arbitrary Plugin Installation and Activation
This record contains material that is subject to copyright
License: Defiant hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute this software vulnerability information. Any copy of the software vulnerability information you make for such purposes is authorized provided that you include a hyperlink to this vulnerability record and reproduce Defiant's copyright designation and this license in any such copy. Read more
License: CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE®). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy. Read more
