CVE-2026-89093

Overview

The Better Messages plugin for WordPress up to version 2.15.33 contains an information exposure vulnerability caused by insecure AI bot identification. Unauthenticated attackers can supply a crafted X-Real-IP header during guest registration to impersonate an internal AI bot account. This logic flaw allows unauthorized access to restricted chat rooms and private message histories.

Description

The Better Messages – Chat Rooms, Group Chat, Private Messages & AI Chat Bots plugin for WordPress is vulnerable to Information Exposure by Spoofing in all versions up to, and including, 2.15.33. This is due to the `is_ai_bot_user()` function identifying privileged internal AI bot accounts by performing a prefix check for `'ai-chat-bot-'` against a guest record's stored IP address, which is populated verbatim from the client-controlled `X-Real-IP` request header during unauthenticated guest registration. This makes it possible for unauthenticated attackers to register a guest identity that the plugin treats as its own internal AI bot, bypassing the per-room role allowlist, draft-status check, and join filters — which are all short-circuited by the bot check in `user_can_join()` and `user_can_read()` — to join administrator-restricted chat rooms, post messages into them, and read the private message history of other users.

Impact

Unauthenticated attackers can bypass role allowlists, draft-status checks, and join filters by spoofing internal AI bot status. This leads to a breach of confidentiality and integrity, enabling unauthorized users to join administrator-restricted chat rooms, post messages, and read private user message histories. System administrators and users relying on chat privacy controls are directly impacted.

Remediation

Update the Better Messages plugin to version 2.15.34 or higher immediately once a patch is released by the vendor. Restrict direct public access to chat functionalities using Web Application Firewall (WAF) rules or reverse proxy configurations that sanitize and validate incoming client headers such as X-Real-IP. Audit existing chat room memberships and logs for anomalous guest registrations or unauthorized bot activity.

Risk context

The vulnerability is rated as medium severity with a CVSS v3 score of 5.3, while the EPSS score of 0.00325 indicates a currently low probability of active exploitation in the wild. However, because it allows unauthorized access to private communications without authentication, defenders should prioritize patching to safeguard sensitive user data.

Affected products

• Better Messages plugin for WordPress