The Quick Playground WordPress plugin is affected by an authorization flaw that allows unauthenticated users to obtain a sync code and upload PHP files via exposed REST API endpoints. This omission in access control enables attackers to perform path‑traversal uploads and subsequently execute arbitrary code on the host server, delivering full control over the application or underlying operating system.

All installations of the Quick Playground plugin developed by davidfcarr running version 1.3.1 or earlier are susceptible. The vulnerability applies to the WordPress REST API implementation that the plugin exposes for synchronization tasks.

The flaw carries a CVSS score of 9.8, indicating a critical severity level. No EPSS score is available, and the vulnerability does not appear in the CISA KEV catalog. Because the attack vector requires only unauthenticated access to the REST API, an attacker can exploit the flaw remotely without any prior user interaction. Successful exploitation results in remote code execution, granting the attacker full integrity and confidentiality compromise of the affected site and potentially the entire web server.