CVE-2021-20813: Sixapart Movable Type

Medium severity, CVSS 6.1. EPSS: 0.9% chance of exploitation in the next 30 days.

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.

Affected products

• Sixapart Movable Type: from 7.0, before 7.8.0 (fixed in 7.8.0)

Published 2021-08-26. Last modified 2026-06-17.