CVE-2026-109209

All-in-One Video Gallery <= 4.9.7 - Authenticated (Subscriber+) Stored Cross-Site Scripting via 'embedcode' Post Meta via XML-RPC

2026-10-27 14:29
poiri3r

Strategic Overview

Status
Patched in 5.0.0
Affected Plugin
All-in-One Video Gallery – Video Player & Galleries for YouTube, Vimeo & Self-Hosted Videos
Affected Version
<= 4.9.7
CVSS
6.4Medium
Weakness type
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE
CVE-2026-109209
View all All-in-One Video Gallery – Video Player & Galleries for YouTube, Vimeo & Self-Hosted Videos vulnerabilities

At a glance

CVE-2026-109209 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the All-in-One Video Gallery WordPress plugin, affecting versions <= 4.9.7. It carries a CVSS score of 6.4 (reachable over the network; low attack complexity). Exploitation requires an authenticated account at Subscriber level or above. The issue is fixed in version 5.0.0; sites on affected versions should update now. Disclosed October 2026, reported by poiri3r.

Vulnerability Overview

The All-in-One Video Gallery – Video Player & Galleries for YouTube, Vimeo & Self-Hosted Videos plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'custom_fields[embedcode]' parameter in all versions up to, and including, 4.9.7 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The sanitization bypass is possible because the save_meta_data() handler returns early when $_POST['post_type'] is absent — a condition always true during XML-RPC requests — and the plugin unconditionally grants Subscribers the publish_aiovg_videos capability, making this exploitable by any authenticated user via a single wp.newPost XML-RPC call.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no interaction from a victim user.

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

All-in-One Video Gallery <= 4.9.7 carries this weakness at custom_fields[embedcode], and reaching it takes an account at Subscriber level or above. Cross-site scripting happens when input from a request is written into a page without being escaped for the context it lands in, so the browser parses attacker-supplied text as markup or script.

Injected script runs with the privileges of whoever views the affected page, which is how these flaws turn into administrator session theft, silent account creation or persistent backdoors in page content. For All-in-One Video Gallery the fix is 5.0.0: builds <= 4.9.7 are affected, anything from 5.0.0 onward is not.

Remediation

Update to version 5.0.0, or a newer patched version

How does WordSec protect against this?

An attacker needs Subscriber access first, so the firewall sees the attempt as traffic from a logged-in account: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: All-in-One Video Gallery 5.0.0 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-109209https://www.wordfence.com/threat-intel/vulnerabilities/id/cc6b1fa7-d5f9-4aec-860e-067c26745450https://nvd.nist.gov/vuln/detail/CVE-2026-109209

Related records

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C