Everest Forms Pro <= 1.9.12 - Unauthenticated Remote Code Execution via Calculation Field
Strategic Overview
- Status
- Patched in 1.9.13
- Affected Plugin
- Everest Forms Pro
- Affected Version
<= 1.9.12- CVSS
- 9.8Critical
- Weakness type
- CWE-94 · Improper Control of Generation of Code ('Code Injection')
- CVE
CVE-2026-3300
At a glance
CVE-2026-3300 is a critical-severity Improper Control of Generation of Code ('Code Injection') vulnerability in the Everest Forms Pro WordPress plugin, affecting versions <= 1.9.12. It carries a CVSS score of 9.8 (reachable over the network; low attack complexity; high confidentiality, integrity, availability impact). Exploitation requires no authentication. The issue is fixed in version 1.9.13; sites on affected versions should update now. Disclosed March 2026, reported by h0xilo.
Vulnerability Overview
The Everest Forms Pro plugin for WordPress is vulnerable to Remote Code Execution via PHP Code Injection in all versions up to, and including, 1.9.12. This is due to the Calculation Addon's process_filter() function concatenating user-submitted form field values into a PHP code string without proper escaping before passing it to eval(). The sanitize_text_field() function applied to input does not escape single quotes or other PHP code context characters. This makes it possible for unauthenticated attackers to inject and execute arbitrary PHP code on the server by submitting a crafted value in any string-type form field (text, email, URL, select, radio) when a form uses the "Complex Calculation" feature.
Technical Analysis
The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user. A successful exploit has high impact on confidentiality, integrity, availability — full site compromise territory.
CWE-94: Improper Control of Generation of Code ('Code Injection')
Everest Forms Pro <= 1.9.12 carries this weakness at process_filter(), and reaching it takes no account at all. Code injection means input from a request reaches a language construct that evaluates code, so the attacker's text is executed rather than treated as data.
The injected code runs with the web server's privileges, giving the attacker the same access to the database and filesystem as WordPress itself. For Everest Forms Pro the fix is 1.9.13: builds <= 1.9.12 are affected, anything from 1.9.13 onward is not.
Remediation
Update to version 1.9.13, or a newer patched version
How does WordSec protect against this?
Requests carrying this pattern arrive without a session, so nothing upstream of the firewall gets a chance to reject them: WordSec's web application firewall inspects request payloads before WordPress loads them. Classes like this one can leave something behind, so the staged malware scanner is the second half: it looks for dropped files and modified code rather than for the request that created them. None of that substitutes for the fix: Everest Forms Pro 1.9.13 closes this, and updating the plugin is the step that ends it.
- Firewall
- Scanner
- Login Security
External References
Related records
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