CVE-2026-100159

CVE-2026-100159 · Popup Box 6.4.1 - 6.4.2 - Unauthenticated Arbitrary Shortcode Execution via Client-IP / X-Forwarded-For HTTP Headers

This page contains facts from public vulnerability sources. Check the original advisory before updating.

The Popup Box plugin for WordPress is vulnerable to Arbitrary Shortcode Execution in versions 6.4.1 to 6.4.2. This is due to the ays_popup_get_user_ip() function reading the client-controlled Client-IP / X-Forwarded-For / Forwarded / X-Forwarded / Forwarded-For request headers, sanitizing them only with sanitize_text_field() (which does not strip the bracket, quote, space, or '=' characters used by shortcode syntax), substituting the value into a popup body wherever the %%user_ip_address%% token appears (a raw str_replace with no escaping in Ays_Pb_Data::replace_message_variables()), and then passing the resulting body to do_shortcode() in Ays_Pb_Public::ays_autoembed() at output on the wp_footer hook. This makes it possible for unauthenticated attackers to execute arbitrary registered shortcodes with attacker-supplied attributes on the server whenever an administrator has added the %%user_ip_address%% token to a popup's Custom Content body, which can be leveraged to read arbitrary data or perform other actions exposed by shortcodes installed on the site.

CVSS 4.8 · Medium · EPSS 0.3%

Published

2026-10-16T02:26:09.256Z

Updated

2026-10-16T15:09:41.509Z

Check your server →