Description
XWiki Platform is a generic wiki platform. Starting in version 14.3-rc-1, `org.xwiki.store.script.TemporaryAttachmentsScriptService#uploadTemporaryAttachment` returns an instance of `com.xpn.xwiki.doc.XWikiAttachment`. This class is not supported to be exposed to users without the `programing` right. `com.xpn.xwiki.api.Attachment` should be used instead and takes case of checking the user's rights before performing dangerous operations. This has been patched in versions 14.9-rc-1 and 14.4.6. There are no known workarounds for this issue.
Remediation
References
https://jira.xwiki.org/browse/XWIKI-20180
https://github.com/xwiki/xwiki-platform/security/advisories/GHSA-8692-g6g9-gm5p
https://github.com/xwiki/xwiki-platform/commit/3c73c59e39b6436b1074d8834cf276916010014d