Improper Neutralization of Directives in Dynamically Evaluated Code ('Eval Injection') in org.xwiki.platform:xwiki-platform-menu-ui

Impact

Any user with view rights on commonly accessible documents including the menu macro can execute arbitrary Groovy, Python or Velocity code in XWiki leading to full access to the XWiki installation due to improper escaping of the macro content and parameters of the menu macro.

The issue can be demonstrated by opening <server>/xwiki/bin/view/Main?sheet=CKEditor.HTMLConverter&language=en&sourceSyntax=xwiki%2F2.1&stripHTMLEnvelope=true&fromHTML=false&toHTML=true&text=%7B%7Bmenu%7D%7D%7B%7Bcache+id%3D%22menuMacro%22%7D%7D%7B%7Bgroovy%7D%7Dprintln%28%22Hello+from+Groovy%21%22%29%7B%7B%2Fgroovy%7D%7D%7B%7B%2Fcache%7D%7D%7B%7B%2Fmenu%7D%7D where <server> is the URL of the XWiki installation. If this displays "Hello from Groovy!", the installation is vulnerable.

Patches

The problem has been patched in XWiki 14.6RC1, 13.10.8 and 14.4.3.

Workarounds

The patch for the document Menu.MenuMacro can be manually applied or a XAR archive of a patched version can be imported. The menu macro was basically unchanged since XWiki 11.6 so on XWiki 11.6 or later the patch for version of 13.10.8 can most likely be applied, on XWiki version 14.0 and later the versions in XWiki 14.6 and 14.4.3 should be appropriate.

References

• https://github.com/xwiki/xwiki-platform/commit/2fc20891e6c6b0ca05ee07e315e7f435e8919f8d
• https://jira.xwiki.org/browse/XWIKI-19857

For more information

If you have any questions or comments about this advisory:

• Open an issue in Jira XWiki.org
• Email us at Security Mailing List