XWiki Platform Wiki UI Main Wiki Eval Injection vulnerability
Date: 2022-09
Affected: maven/org.xwiki.platform:xwiki-platform-wiki-ui-mainwiki, maven/org.xwiki.platform:xwiki-platform-wiki-ui-mainwiki
Attack vector: rce
Category: vulnerability-disclosure
Severity: Critical
CVE: CVE-2022-36099
CWE: CWE-116
CWE-94
CWE-95
CVSS: 9.9 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H)

### Impact It's possible to inject arbitrary wiki syntax including Groovy, Python and Velocity script macros via the request (URL parameter) using the `XWikiServerClassSheet` if the user has view access to this sheet and another page that has been saved with programming rights, a standard condition on a public read-only XWiki installation or a private XWiki installation where the user has an account. This allows arbitrary Groovy/Python/Velocity code execution which allows bypassing all rights checks and thus both modification and disclosure of all content stored in the XWiki installation. Also, this could be used to impact the availability of the wiki. On current versions (e.g., 14.3), this can be triggered by opening the URL `/xwiki/bin/view/Main/?sheet=XWiki.XWikiServerClassSheet&form_token=<form_token>&action=delete&domain=foo%22%2F%7D%7D%7B%7Basync%20async%3D%22true%22%20cached%3D%22false%22%20context%3D%22doc.reference%22%7D%7D%7B%7Bgroovy%7D%7Dprintln(%22hello%20from%20groovy!%22)%7B%7B%2Fgroovy%7D%7D%7B%7B%2Fasync%7D%7D`, on version 5.3 Milestone 2 (oldest impacted version), the issue can be reproduced using `<server>/xwiki/bin/view/Main/?sheet=WikiManager.XWikiServerClassSheet&form_token=<form_token>&action=delete&domain=foo%22%2F%7D%7D%7B%7B%2Ferror%7D%7D%7B%7B%2Fhtml%7D%7D%7B%7Bfootnote%7D%7D%7B%7Bgroovy%7D%7Dprintln%28%22hello+from+groovy%21%22%29%7B%7B%2Fgroovy%7D%7D%7B%7B%2Ffootnote%7D%7D`. In both cases `<server>` is the URL of the XWiki installation and `<form


Mitigations:

Architectural layers (MAESTRO):