WordPress before 5.2.3 allows XSS in media uploads because wp_ajax_upload_attachment is mishandled.
https://www.debian.org/security/2020/dsa-4677
https://www.debian.org/security/2020/dsa-4599
https://wordpress.org/news/2019/09/wordpress-5-2-3-security-and-maintenance-release/
https://seclists.org/bugtraq/2020/Jan/8
https://lists.debian.org/debian-lts-announce/2019/10/msg00023.html