CVE-2026-3576: Planyo Online Reservation System: Server-Side Request Forgery leading to Local File Inclusion

Planyo Online Reservation System: Server-Side Request Forgery leading to Local File Inclusion

The Planyo Online Reservation System plugin for WordPress is vulnerable to Server-Side Request Forgery leading to Local File Inclusion in all versions up to, and including, 3.0. The ulap.php file acts as an AJAX proxy and is directly accessible without WordPress bootstrapping or any authentication. The send_http_post() function validates the host of the provided URL against an allowlist that includes 'localhost', but critically fails to validate the URL scheme/protocol. This makes it possible for unauthenticated attackers to supply a file:// URL (e.g., file://localhost/etc/passwd) which bypasses the host allowlist check because parse_url() returns 'localhost' as the host. The URL is then passed to curl_init() or fopen(), both of which support the file:// protocol, allowing the attacker to read arbitrary local files on the server and have their contents returned in the HTTP response. This can lead to disclosure of sensitive files such as /etc/passwd, wp-config.php (containing database credentials and authentication keys), and other server-side files.

Description from the National Vulnerability Database, published by Wordfence

What it means for a small business

Planyo Online Reservation System is a WordPress plugin. If your website uses it, the flaw is on your site whether or not anyone has noticed yet: attackers scan the whole internet for the plugins with published flaws, usually within days of a record like this one going public.

Most small-business sites run 15 to 40 plugins, and few owners know the list. You can check from WordPress itself (Plugins, then Installed Plugins), or let our free plugin check look it up by name.

Check your own setup

Is Planyo Online Reservation System on the danger list? Our free plugin check shows every recorded flaw for it and the version that fixes each.
Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

Weekly security brief

The flaws that hit local websites, every Friday.

One short email: what got exploited this week, which WordPress plugins broke, and what to check. Unsubscribe in one click.