CVE-2026-100159

Description

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.

References

• https://plugins.trac.wordpress.org/browser/ays-popup-box/tags/6.4.2/includes/class-ays-pb-data.php#L79
• https://plugins.trac.wordpress.org/browser/ays-popup-box/tags/6.4.2/public/class-ays-pb-public.php#L3389
• https://plugins.trac.wordpress.org/browser/ays-popup-box/tags/6.4.2/public/partials/ays-pb-public-templates.php#L4299
• https://plugins.trac.wordpress.org/browser/ays-popup-box/tags/6.4.2/public/partials/ays-pb-public-templates.php#L4560
• https://plugins.trac.wordpress.org/browser/ays-popup-box/tags/6.4.2/public/partials/ays-pb-public-templates.php#L69