CVE-2025-3439
Published: 11 April 2025
Summary
CVE-2025-3439 is a critical-severity Deserialization of Untrusted Data (CWE-502) vulnerability in Wpeverest Everest Forms. Its CVSS base score is 9.8 (Critical).
Operationally, ranked in the top 18.1% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
Deeper analysis
The Everest Forms plugin for WordPress, used for building contact forms, quizzes, surveys, and similar features, is affected by a PHP Object Injection vulnerability (CWE-502) in all versions through 3.1.1. The flaw stems from unsafe deserialization of untrusted data supplied in the field_value parameter, allowing an attacker to supply a serialized PHP object without authentication.
Unauthenticated remote attackers can supply crafted input to inject arbitrary PHP objects. Although the plugin itself contains no usable POP chain, the presence of a vulnerable chain from any other installed plugin or theme on the site can enable follow-on actions such as arbitrary file deletion, sensitive data disclosure, or remote code execution, consistent with the CVSS 9.8 rating.
Public references point to a patched changeset (3268742) in the WordPress plugin repository and a detailed advisory from Wordfence that identify the affected code path in html-admin-page-entries-view.php; administrators are therefore expected to apply the vendor update to eliminate the deserialization sink.
EPSS scores for the CVE rose from a low baseline to a recorded peak of 0.0448, indicating measurable growth in exploitation interest after public disclosure.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-10803
Vulnerability details
The Everest Forms – Contact Form, Quiz, Survey, Newsletter & Payment Form Builder for WordPress plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 3.1.1 via deserialization of untrusted input from the 'field_value'…
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parameter. This makes it possible for unauthenticated attackers to inject a PHP Object. No known POP chain is present in the vulnerable software, which means this vulnerability has no impact unless another plugin or theme containing a POP chain is installed on the site. If a POP chain is present via an additional plugin or theme installed on the target system, it may allow the attacker to perform actions like delete arbitrary files, retrieve sensitive data, or execute code depending on the POP chain present.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Penetration testing supplies malicious serialized objects, detecting unsafe deserialization and supporting corrective actions.
Evaluation of untrusted data handling (deserialization testing) reveals unsafe processing, which the required remediation process addresses.
Untrusted serialized data can be deserialized and observed inside the chamber, blocking gadget-chain exploitation outside the sandbox.
Validates or rejects untrusted serialized data before deserialization occurs.
Identifies and blocks malicious code introduced through deserialization of untrusted data at system boundaries.
Integrity verification of serialized information can detect tampering before deserialization occurs.
Provenance of associated data allows detection of untrusted sources before deserialization or processing occurs.