WordPress security changelog
HIGH CVE-2026-81807 Deferred

Simple Ajax Chat permits unauthenticated stored cross-site scripting

Simple Ajax Chat before 20260827 renders chat messages without adequate escaping. An unauthenticated visitor can inject HTML attributes and script that executes in the browser of anyone viewing the chat, including an administrator.

CVE / CNA score 8.8 CVSS 3.1 · 134c704f-9b21-4f2e-91b3-4a467353bcc0
NVD score Pending NVD has not published its own CVSS assessment.
Component
Simple Ajax Chat
Plugin slug
simple-ajax-chat
Affected
< 20260827
Safe version
20260827
Published
Sep 02, 2026
Weakness
CWE-79 — Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

This CVE was published Sep 02, 2026 and is one of 9 known issues for this plugin.

Update, patch or deactivate.

Update to Simple Ajax Chat 20260827 or later, remove malicious chat messages, and invalidate privileged sessions if administrators viewed affected chat content.

A safe version is available, so updating to that version or later is the preferred remediation. If an immediate update is not practical, consider a targeted application patch or temporarily restricting the affected functionality.

Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.

Technical description

The Simple Ajax Chat WordPress plugin before 20260827 does not escape chat message content before rendering it, allowing unauthenticated users to inject arbitrary HTML attributes into the page and run scripts in the browser of anyone viewing the chat, including administrators.

CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Primary and upstream sources