Quick Playground Plugin Vulnerability (CVE-2026-6403)

6 months ago

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Security Alert Summary

The Quick Playground plugin for WordPress contains a path traversal vulnerability in versions up to and including 1.3.3. Insufficient path validation in the qckply_zip_theme() function allows a user-controlled stylesheet parameter to be appended to the theme root path without sanitizing directory traversal sequences. An unauthenticated attacker can trigger creation of a ZIP archive containing arbitrary files from the server filesystem – including wp-config.php.

CVE Details

CVE ID: CVE-2026-6403
Affected component: Quick Playground plugin for WordPress
Affected versions: Versions up to and including 1.3.3
Published: May 15, 2026 at 09:16:16 AM
Last modified: May 15, 2026 at 02:09:15 PM
CVSS v3.1: Base Score 7.5 – HIGH; Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Authentication / Privileges / User interaction: No authentication required; Privileges Required: NONE; User Interaction: NONE
Primary impact: Confidentiality: HIGH; Integrity: NONE; Availability: NONE
Weakness: CWE-22 (Path Traversal)

Technical Details

This vulnerability is a path traversal issue caused by insufficient validation of a user-controlled input. The plugin function qckply_zip_theme() appends the stylesheet parameter directly to the theme root directory path without removing or rejecting directory traversal sequences such as “..”. Because the parameter is not sanitized, an attacker can construct a path that references files outside the intended theme directory.

When the vulnerable code processes the crafted stylesheet value, it can include arbitrary filesystem paths in the ZIP archive creation process. The CVE description notes that this can allow an attacker to cause creation of a ZIP archive containing arbitrary files from the server filesystem, including wp-config.php. The vulnerability is exploitable over the network without authentication, given the CVSS vector.

How This Could Impact Your Website

In a realistic scenario, an external attacker could exploit this issue without logging in. A site owner or administrator who has installed Quick Playground may have internal staff or external contractors who expect theme-related utilities to only access theme files. An unauthenticated request that leverages the vulnerable parameter could result in a downloadable ZIP that includes sensitive configuration files. Those files can contain database credentials and internal email addresses for site users or staff.

Possible practical consequences include exposure of internal user email addresses and configuration details, which increases the risk of targeted phishing or social engineering against site staff or contractors. The vulnerability does not indicate integrity or availability impact in the CVSS data, so it should not be assumed to permit code modification or site downtime based on the provided information.

If you\’re unsure whether your site is affected or how to assess your current user roles and plugins, it may be worth having a professional review your setup.

Recommended Actions

Update the affected plugin as soon as a patched version is available.
Review and reduce unnecessary user roles, especially contributor-level or other roles that can be granted to external contractors.
Enforce strong passwords and enable two-factor authentication for editors and administrators.
Remove unused or unmaintained plugins from your site.
Monitor site activity and access logs for unusual behavior or requests that attempt directory traversal patterns.

If you\’d like help reviewing your plugins, user roles, or overall WordPress security posture, our team at Freshy is happy to help.

References

Nick Paliughi https://freshysites.com/team/nick-paliughi/

Nick was born in California and now resides in Lake Worth, FL. He has 10 years of experience building and maintaining sites in WordPress, which he is excited to put to use at Freshy. Prior to starting at Freshy in 2022 his focus was on WordPress security & malware removal. When he’s not tending to your website, Nick is installing exhibitions at art galleries and museums in Palm Beach County, and if he’s lucky surfing at the Lake Worth pier.