CVE-2021-20813
Cross-site scripting vulnerability in Edit screen of Content Data of Movable Type (Movable Type 7 r.4903 and earlier (Movable Type 7 Series) and Movable Type Advanced 7 r.4903 and earlier (Movable Type Advanced 7 Series)) allows remote attackers to inject arbitrary script or HTML via unspecified vectors.
Source: CVE-2021-20813