Impact

When login via the OAuth method, the identityOAuth parameters, sent in a GET request is vulnerable to XSS and XWiki syntax injection. This allows remote code execution via the groovy macro and thus affects the confidentiality, integrity and availability of the whole XWiki installation.

The vulnerability is in this part of the code.

Patches The issue has been fixed in Identity OAuth version 1.6 by https://github.com/xwikisas/identity-oauth/commit/d805d3154b17c6bf455ddf5deb0a3461a3833bc6 . The fix is in the content of the IdentityOAuth/LoginUIExtension file

Workarounds There are no known workarounds besides upgrading.

References Are there any links users can visit to find out more?

Original report: https://jira.xwiki.org/browse/XWIKI-20719