The host is installed with Atlassian Confluence Server before 7.13.17, 7.14.0 before 7.19.9, or 7.20.0 before 8.2.2 and is prone to a broken access control vulnerability. A flaw is present in the application which fails to properly handle attatchments feature. Successful exploitation allows remote attackers who have read permissions to a page, but not write permissions, to upload attachments.