CVE-2026-3367 Cross-site scripting in Lockme calendars integration
Authenticated administrators can inject arbitrary scripts via plugin settings, enabling XSS attacks against other users in WordPress multisite environments.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-3367?
CVE-2026-3367 is a medium-severity cross-site scripting vulnerability in lustmored Lockme calendars integration, published on 11 Jul 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
The Lockme OAuth2 calendars integration plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'App ID' setting in all versions up to, and including, 2.11.0. This is due to insufficient input sanitization and output escaping. The register_setting() call on line 197 lacks a sanitize callback, allowing unsanitized data to be stored via update_option(). When the settings page is rendered, the stored value is echoed directly into an HTML input's value attribute without esc_attr() on line 212. This makes it possible for authenticated attackers, with administrator-level access and above, to inject arbitrary web scripts in the settings page that will execute whenever a user accesses the plugin settings page. Multiple fields are affected: App ID (client_id), App Secret (client_secret), Bookings ID prefix (id_prefix), and API domain (api_domain). This vulnerability is particularly impactful in WordPress multisite installations where administrators of individual sites should not be able to execute JavaScript affecting other users.
Weakness: CWE-79
Which versions are affected by CVE-2026-3367?
How do I fix CVE-2026-3367?
No fix has been published for CVE-2026-3367 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-3367 being exploited?
There is no known exploitation of CVE-2026-3367 in the wild and no public exploit code.
Sources
Also known as GHSA-6q4h-2q4c-jmg7.