Executive brief
The ProSolution WP Client WordPress plugin allows authenticated users (including subscribers) to make arbitrary HTTP requests to internal networks through a vulnerable URL validation function. An attacker with a subscriber account can bypass internal firewalls, enumerate internal services, and potentially modify or delete data on internal systems by injecting custom HTTP requests.
Technical details
The plugin's proSol_url_validate AJAX action does not validate user-supplied URLs or check user capabilities/nonce before performing server-side HTTP requests. An authenticated attacker can exploit this server-side request forgery (SSRF) vulnerability by crafting malicious requests to internal hosts. The userval parameter is concatenated unsanitized into request headers, allowing CRLF injection to append arbitrary HTTP requests and methods (e.g., DELETE) to internal services. Exploitation requires only an authenticated account (subscriber level) and no special configuration. The vulnerability was patched in version 2.0.9.
Affected products
- ProSolution WP Client before 2.0.9
Timeline
- 2026-08-10: disclosed
- 2026-08-12: patched: Fixed in version 2.0.9