CVE-2026-123478: Meow Apps AI Engine stored XSS in plugin

Q: Is CVE-2026-123478 being exploited?

It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.

Q: What does this mean?

This is a stored cross-site scripting flaw, meaning attackers can inject malicious scripts into the site. The advisory says these scripts can steal visitor data or hijack accounts.

Q: Am I affected, and how do I check?

AI Engine plugin version 3.9.1 and earlier, published by Meow Apps for WordPress, is listed as vulnerable. To check the installed version, look at the Plugins page in the WordPress admin or the plugin's version number.

Q: How do I fix CVE-2026-123478?

Update the WordPress AI Engine plugin to version 3.9.2 or later, which is the fixed release. The sources do not list a workaround.

Summary

Stored cross-site scripting in the Meow Apps AI Engine (ai-engine) WordPress plugin lets an attacker plant malicious script that runs in a user's browser. The attack can be launched remotely without logging in, but it requires a user to take an action, such as opening a crafted page.

Read the original description

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Meow Apps AI Engine ai-engine allows Stored XSS.This issue affects AI Engine: from n/a through 3.9.1.

Who should check

Teams running the WordPress AI Engine plugin (ai-engine) version 3.9.1 or earlier, such as WordPress site operators and hosts

Read the source excerpt

“<= 3.9.1 Vulnerable version(s)”

patchstack.com

cve.now Index

19Pcve.now Index 19 of 100 · methodology v3 · provisional

Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
Exposure12/25Specific setups only, reachable over the network without a login
Reach?/20Unknown. No tracked technology or package matched
Severity7.1/10CVSS 7.1
No patch0/5No signal

What would change the score

Would score about 69 if added to CISA KEV
Would score about 64 if CISA's SSVC rates exploitation active

How the score works · Rankings

What to do

Check whether your setup matches what the bug needs.
AI Engine plugin version 3.9.1 or earlier
Upgrade to a fixed version: 3.9.2.

Check your systems with an agent

Paste this into a coding or ops agent. It checks your systems read-only and reports a table per asset.

Check whether my systems are affected by CVE-2026-123478 (WordPress AI Engine plugin <= 3.9.1 - Cross Site Scripting (XSS) vulnerability), using the cve.now data below.

Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only.

What cve.now has for CVE-2026-123478 (entry last updated 2026-11-11):
Affected:
- Meow Apps AI Engine: through 3.9.1
Fixed versions: 3.9.2.
Conditions (all must be true for the bug to be hit):
- AI Engine plugin version 3.9.1 or earlier (source: https://patchstack.com/database/wordpress/plugin/ai-engine/vulnerability/wordpress-ai-engine-plugin-3-9-1-cross-site-scripting-xss-vulnerability?_s_id=cve)
Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory.
Attacker needs: network access, no login, a user action.
CISA KEV: CVE-2026-123478 is not listed as of cve.now's last read.
This KEV status is for CVE-2026-123478 only. If you also check another CVE, look up its own KEV status; never assume it from this one.

How to check:
- Installed software: check what is actually running, not what a repo declares. Read the version from each host, container image and Kubernetes node (the binary's version output, the OS package database, image layers), and check whether the conditions above hold there. Distribution packages may carry a backported fix under an older version number; confirm against the distribution's own advisory.

Verify against the linked advisories before concluding, and cite the date you read each one:
- https://patchstack.com/database/wordpress/plugin/ai-engine/vulnerability/wordpress-ai-engine-plugin-3-9-1-cross-site-scripting-xss-vulnerability?_s_id=cve
- https://www.cve.org/CVERecord?id=CVE-2026-123478
Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing.

Entry: https://cve.now/CVE-2026-123478
For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example get_vulnerability with id CVE-2026-123478.

Timeline

Nov 11, 2026, 11:00 AM UTCCVE published
Nov 11, 2026, 11:04 AM UTCFirst seen by cve.now
Nov 11, 2026, 1:30 PM UTCRecord last updated

Affected versions

ai-engine
through 3.9.1

Evidence 3

CVE record · 2

Establishes: The identifier and description.

Record
CVE List · CVE-2026-123478
Record
NVD · CVE-2026-123478

Corrections

None so far.

Something wrong on this page? Report an error. Every fix is listed here.

Questions about CVE-2026-123478

Is CVE-2026-123478 being exploited?

It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data

What does this mean?

This is a stored cross-site scripting flaw, meaning attackers can inject malicious scripts into the site. The advisory says these scripts can steal visitor data or hijack accounts.Source: patchstack.com, cve.org

Which versions are affected by CVE-2026-123478?

ai-engine: through 3.9.1.Source: cve.now feed data

Am I affected, and how do I check?

AI Engine plugin version 3.9.1 and earlier, published by Meow Apps for WordPress, is listed as vulnerable. To check the installed version, look at the Plugins page in the WordPress admin or the plugin's version number.Source: patchstack.com, cve.org

How do I fix CVE-2026-123478?

Update the WordPress AI Engine plugin to version 3.9.2 or later, which is the fixed release. The sources do not list a workaround.Source: patchstack.com, cve.org

WordPress AI Engine plugin <= 3.9.1 - Cross Site Scripting (XSS) vulnerability