CVE-2026-66583: CWE-502 Deserialization of Untrusted Data in WPMU DEV Forminator
Description
CVE-2026-66583 is a critical vulnerability in WPMU DEV's Forminator plugin, affecting versions up to and including 1.57.0. It involves unauthenticated PHP object injection due to deserialization of untrusted data, which can lead to full compromise of confidentiality, integrity, and availability.
CVSS v3.1
Score 9.8critical
Affected software
WPMU DEV
Forminator
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-66583) is a deserialization of untrusted data issue (CWE-502) in the Forminator plugin by WPMU DEV. It allows unauthenticated attackers to perform PHP object injection, potentially leading to remote code execution or other severe impacts. The CVSS 3.1 base score is 9.8, indicating critical severity with network attack vector, low attack complexity, no privileges required, and no user interaction needed. The vulnerability affects Forminator versions up to 1.57.0.
Potential Impact
Successful exploitation can result in complete compromise of the affected system, including full confidentiality, integrity, and availability impacts. Attackers can execute arbitrary PHP code remotely without authentication.
Mitigation Recommendations
No patch or official fix information is provided in the input data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid using affected versions or apply any recommended temporary mitigations from the vendor.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Patchstack
- Date Reserved
- 2026-07-27T14:00:04.572Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6a86f1abacd9273b49977b76
Added to database: 08/20/2026, 12:23:07 UTC
Last enriched: 09/11/2026, 01:31:59 UTC
Last updated: 10/05/2026, 06:48:18 UTC
Views: 55
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