CVE-2026-15098

GHSA-4vrv-fq2h-vgq6

The Real3D Flipbook Lite plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'lightboxtext' shortcode attribute (and other unsanitized attributes handled by on_shortcode()) in versions up to, and including, 5.1.1. This is due to insufficient input sanitization and output escaping in the on_shortcode() and print_global_options() functions: shortcode attribute values are copied verbatim into $this->flipbook_options and then emitted via wp_json_encode() inside a <script type="application/json"> block without the JSON_HEX_TAG flag, allowing a literal </script> byte sequence in the attribute value to break out of the JSON script context. Because WordPress's shortcode_parse_atts() applies stripcslashes() to attribute values, an attacker can encode the breakout tag as \x3c/script\x3e\x3cscript\x3e…\x3c/script\x3e, which survives the wp_kses_post save-time filter applied to Contributor content (the escape bytes are safe text characters, not HTML tags) and is decoded ...