WP Photo Album Plus is vulnerable to stored Cross-Site Scripting in all versions up to, and...

WP Photo Album Plus is vulnerable to stored Cross-Site Scripting in all versions up to, and including, 9.2.03.001 through a decode-after-sanitize (double-encoding) flaw in the photo-comment pipeline. On write, wppa_do_comment() sanitizes the comment with wppa_filter_html() (wp_kses) followed by wp_strip_all_tags() (wppa-functions.php:2623-2624). Because wp_strip_all_tags() only removes real tags, an attacker who submits a double HTML-entity-encoded payload (e.g. <img src=... onload=...>) passes the write filters as harmless entity text and is stored one decode-level down (<img ... onload=...>).