Payload is a free and open source headless content management system. In versions before 3.90.0 and canary versions before 4.0.0-canary.34, local upload configurations that accept XML files can store an XML file and stylesheet that execute JavaScript in the Payload origin when a logged-in user opens the file. This issue is fixed in versions 3.90.0 and 4.0.0-canary.34.
Analyzing vulnerability vectors…