Package Instance

XWiki.WebHome vulnerable to Improper Privilege Management in XWiki resolving groups
### Impact

It's possible to exploit a bug in XWikiRights resolution of groups to obtain privilege escalation. 

More specifically, editing a right with the object editor leads to adding a supplementary empty value to groups which is then resolved as a reference to XWiki.WebHome page. Adding an XWikiGroup xobject to that page then transforms it to a group, any user put in that group would then obtain the privileges related to the edited right.

Note that this security issue is normally mitigated by the fact that XWiki.WebHome (and XWiki space in general) should be protected by default for edit rights. 

### Patches

The problem has been patched in XWiki 13.10.4 and 14.2RC1 to not consider anymore empty values in XWikiRights. 

### Workarounds

It's possible to workaround the problem by setting appropriate rights on XWiki.WebHome page to prevent users to edit it. 

### References

* https://jira.xwiki.org/browse/XWIKI-18386
* https://jira.xwiki.org/browse/XWIKI-15776

### For more information
If you have any questions or comments about this advisory:
* Open an issue in [Jira XWiki.org](https://jira.xwiki.org)
* Email us at [Security Mailing List](mailto:security@xwiki.org)

org.xwiki.platform:xwiki-platform-oldcore Open Redirect vulnerability
### Impact

It is possible to bypass the existing security measures put in place to avoid open redirect by using a redirect such as `//mydomain.com` (i.e. omitting the `http:`). It was also possible to bypass it when using URL such as `http:/mydomain.com`.

### Patches
The problem has been patched on XWiki 13.10.10, 14.4.4 and 14.8RC1.

### Workarounds
The only way to workaround the bug is by providing a patched jar of xwiki-platform-oldcore containing the following changes: https://github.com/xwiki/xwiki-platform/commit/e4f7f68e93cb08c25632c126356d218abf192d1e#diff-c445f288d5d63424f56ef13f65514ab4e174a72e979b53b88197c2b7def267cf.

### References

 * Jira ticket of the reported vulnerability: https://jira.xwiki.org/browse/XWIKI-19994
 * Jira ticket of the original mechanism put in place to prevent open redirect: https://jira.xwiki.org/browse/XWIKI-10309
 * Original advisory about open redirect: https://github.com/xwiki/xwiki-platform/security/advisories/GHSA-jp55-vvmf-63mv

### For more information
If you have any questions or comments about this advisory:
* Open an issue in [Jira](https://jira.xwiki.org)
* Email us at [Security ML](mailto:security@xwiki.org)

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
XWiki Platform is a generic wiki platform offering runtime services for applications built on top of it. Any user who can edit their own user profile can execute arbitrary script macros including Groovy and Python macros that allow remote code execution including unrestricted read and write access to all wiki contents. The same vulnerability can also be exploited in other contexts where the `display` method on a document is used to display a field with wiki syntax, for example in applications created using `App Within Minutes`. This has been patched in XWiki 13.10.11, 14.4.8, 14.10.2 and 15.0RC1. There is no workaround apart from upgrading.

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
XWiki Platform is a generic wiki platform offering runtime services for applications built on top of it. In affected versions it's possible to display or interact with any page a user cannot access through the combination of the async and display macros. A comment with either macro will be executed when viewed providing a code injection vector in the context of the running server. This vulnerability has been patched in XWiki 15.0-rc-1, 14.10.3, 14.4.8, and 13.10.11. Users are advised to upgrade. There are no known workarounds for this issue.

org.xwiki.platform:xwiki-platform-oldcore vulnerable to data leak through deleted documents
### Impact

Rights added to a document are not taken into account for viewing it once it's deleted. Note that this vulnerability only impact deleted documents that where containing view rights: the view rights provided on a space of a deleted document are properly checked.

### Patches

The problem has been patched in XWiki 14.10 by checking the rights of current user: only admin and deleter of the document are allowed to view it.

### Workarounds

There is no workaround for this vulnerability other than upgrading.

### References

 * Jira ticket: https://jira.xwiki.org/browse/XWIKI-16285
 * Commit: https://github.com/xwiki/xwiki-platform/commit/d9e947559077e947315bf700c5703dfc7dd8a8d7

### For more information
If you have any questions or comments about this advisory:
* Open an issue in [Jira](https://jira.xwiki.org)
* Email us at [security ML](mailto:security@xwiki.org)

XWiki Platform subject to Uncontrolled Resource Consumption
XWiki Platform is a generic wiki platform offering runtime services for applications built on top of it. It's possible to make the farm unusable by adding an object to a page with a huge number (e.g. 67108863). Most of the time this will fill the memory allocated to XWiki and make it unusable every time this document is manipulated. This issue has been patched in XWiki 14.0-rc-1.