xtreeme Planyo Online Reservation System Plugin up to 3.0 on WordPress AJAX Proxy ulap.php send_http_post url input validation

Summaryinfo

A vulnerability described as problematic has been identified in xtreeme Planyo Online Reservation System Plugin up to 3.0. The affected element is the function send_http_post of the file ulap.php of the component AJAX Proxy. Executing a manipulation of the argument url can lead to input validation. This vulnerability is handled as CVE-2026-3576. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in xtreeme Planyo Online Reservation System Plugin up to 3.0. It has been declared as problematic. This vulnerability affects the function send_http_post of the file ulap.php of the component AJAX Proxy. The manipulation of the argument url with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect confidentiality. CVE summarizes:

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.

The advisory is available at wordfence.com. This vulnerability was named CVE-2026-3576 since 03/04/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 07/11/2026).

By approaching the search of inurl:ulap.php it is possible to find vulnerable targets with Google Hacking.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-43137). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• WordPress Plugin

Vendor

• xtreeme

Name

• Planyo Online Reservation System Plugin

Version

• 3.0

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

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Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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