Auth bypass in Wordplus Better Messages – Chat Rooms, Group Chat, Private & Ai Bots
CVE-2026-89093
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.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.006 (46.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 47th percentile — 46.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000
Affected products
Weakness classification (CWE)
References
- www.wordfence.com/threat-intel/vulnerabilities/id/df28ecd7-d463-48b7-95e6-8adc9…
- plugins.trac.wordpress.org/browser/bp-better-messages/tags/2.15.33/inc/function…
- plugins.trac.wordpress.org/browser/bp-better-messages/tags/2.15.33/inc/chats.php
- plugins.trac.wordpress.org/browser/bp-better-messages/tags/2.15.33/inc/chats.php
- plugins.trac.wordpress.org/browser/bp-better-messages/tags/2.15.33/inc/chats.php
- plugins.trac.wordpress.org/browser/bp-better-messages/tags/2.15.33/inc/guests.p…
- plugins.trac.wordpress.org/browser/bp-better-messages/tags/2.15.33/inc/guests.p…
- plugins.trac.wordpress.org/browser/bp-better-messages/tags/2.15.33/inc/guests.p…
- plugins.trac.wordpress.org/changeset
Frequently asked questions
- What is CVE-2026-89093?
- CVE-2026-89093 is a medium-severity vulnerability in Wordplus Better Messages – Chat Rooms, Group Chat, Private & Ai Bots, classified under Improper Authentication. CVSS score: 5.3/10. Published 2026-09-19.
- How severe is CVE-2026-89093?
- Medium severity. CVSS v3 base score is 5.3 out of 10.