CVE-2026-8787

high

Description

The Firebase Support & Chat Management plugin for WordPress is vulnerable to privilege escalation in all versions up to, and including, 3.1.1. This is due to the `firebase_auth()` function authenticating the request as the WordPress user whose email is supplied in the `user_email` POST parameter without verifying ownership of that email (no Firebase ID token signature/issuer/audience verification). This makes it possible for authenticated attackers, with Subscriber-level access and above, to log in as an arbitrary existing user — including an Administrator — by submitting that user's email address to the `acb_firebase_auth` AJAX action, resulting in full account takeover.

References

https://www.wordfence.com/threat-intel/vulnerabilities/id/90783d75-a255-4133-ac7b-32e0a70c8c69?source=cve

https://plugins.trac.wordpress.org/browser/admin-chat-box/trunk/inc/ACB_AjaxHandler.php#L338

https://plugins.trac.wordpress.org/browser/admin-chat-box/trunk/inc/ACB_AjaxHandler.php#L237

https://plugins.trac.wordpress.org/browser/admin-chat-box/tags/3.1.1/inc/ACB_AjaxHandler.php#L338

https://plugins.trac.wordpress.org/browser/admin-chat-box/tags/3.1.1/inc/ACB_AjaxHandler.php#L237

Details

Source: Mitre, NVD

Published: 2026-05-27

Updated: 2026-05-27

Risk Information

CVSS v2

Base Score: 9

Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:C

Severity: High

CVSS v3

Base Score: 8.8

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Severity: High

EPSS

EPSS: 0.00042