XSS in Wpeverest Everest Forms – Contact Form, Payment Quiz, Survey & Custom Form Builder With Ai

CVE-2026-91152

The Everest Forms – Contact Form, Payment Form, Quiz, Survey & Custom Form Builder with AI plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'evf_toast_type' parameter in all versions up to, and including, 3.6.2 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link. Exploitation requires the sibling evf_toast parameter to decode successfully via atob(), but this is a trivially attacker-controlled prerequisite.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (28.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 28th percentile — 28.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

The 30-day trend appears once there are two daily scores.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-91152?
CVE-2026-91152 is a medium-severity vulnerability in Wpeverest Everest Forms – Contact Form, Payment Quiz, Survey & Custom Form Builder With Ai, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-10-29.
How severe is CVE-2026-91152?
Medium severity. CVSS v3 base score is 6.1 out of 10.