XWiki OIDC Authenticator vulnerable to bypassing OpenID login by providing a custom provider

Impact

Even if a wiki has an OpenID provider configured through its xwiki.properties, it is possible to provide a third party provider by providing its details through request parameters. One can then bypass the XWiki authentication altogether by specifying its own provider through the oidc.endpoint.* request parameters (or by using an XWiki-based OpenID provider with oidc.xwikiprovider.

With the same approach, one could also provide a specific group mapping through oidc.groups.mapping that would make his user automatically part of the XWikiAdminGroup

Patches

Patched in version 1.29.1.

Workarounds

There is no workaround, an upgrade of the authenticator is required.

References

https://jira.xwiki.org/browse/OIDC-118

For more information

If you have any questions or comments about this advisory:

• Open an issue in Jira XWiki
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