CVE-2026-3296: wordpress everest-forms Deserialization of Untrusted Data

Vulnerability summary

CVE-2026-3296 is a critical (CVSS 9.8) Deserialization of Untrusted Data vulnerability in wordpress everest-forms. EPSS estimates a 2.98% chance of exploitation in the next 30 days, higher than 87.1% of scored vulnerabilities. Fixed in 3.4.4.

Timeline

1. 08-04-2026
   PublishedVulnerability first disclosed.
2. 08-04-2026
   Last modifiedVulnerability information updated.

Description

The Everest Forms plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 3.4.3 via deserialization of untrusted input from form entry metadata. This is due to the html-admin-page-entries-view.php file calling PHP's native unserialize() on stored entry meta values without passing the allowed_classes parameter. This makes it possible for unauthenticated attackers to inject a serialized PHP object payload through any public Everest Forms form field. The payload survives sanitize_text_field() sanitization (serialization control characters are not stripped) and is stored in the wp_evf_entrymeta database table. When an administrator views entries or views an individual entry, the unsafe unserialize() call processes the stored data without class restrictions.

• CWE-502Deserialization of Untrusted DataThe product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.