CVE-2023-26477
📋 TL;DR
This vulnerability allows remote code execution via injection of arbitrary wiki syntax including Groovy, Python, and Velocity script macros through the 'newThemeName' URL parameter in XWiki Platform. Attackers can execute arbitrary code on the server with the privileges of the XWiki application. All XWiki Platform instances running affected versions are vulnerable.
💻 Affected Systems
- XWiki Platform
📦 What is this software?
Xwiki by Xwiki
Xwiki by Xwiki
Xwiki by Xwiki
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise allowing attackers to execute arbitrary code, access sensitive data, modify content, and potentially pivot to other systems.
Likely Case
Remote code execution leading to data theft, website defacement, or installation of backdoors.
If Mitigated
Limited impact with proper input validation and output encoding, but still potentially serious if other controls fail.
🎯 Exploit Status
Exploitation requires only URL parameter manipulation with no authentication needed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 13.10.10, 14.4.6, or 14.9-rc-1 and later
Vendor Advisory: https://github.com/xwiki/xwiki-platform/security/advisories/GHSA-x2qm-r4wx-8gpg
Restart Required: Yes
Instructions:
1. Backup your XWiki instance. 2. Upgrade to patched version (13.10.10, 14.4.6, or 14.9-rc-1+). 3. Restart the XWiki application server. 4. Verify the fix by checking version and testing the vulnerability.
🔧 Temporary Workarounds
Manual patch application
allEdit FlamingoThemesCode.WebHomeSheet to apply the same changes as the official patch
Edit FlamingoThemesCode.WebHomeSheet file and apply changes from commit ea2e615f50a918802fd60b09ec87aa04bc6ea8e2
🧯 If You Can't Patch
- Implement WAF rules to block requests containing suspicious 'newThemeName' parameter values
- Restrict network access to XWiki instance to trusted IP addresses only
🔍 How to Verify
Check if Vulnerable:
Check if your XWiki version falls within affected ranges and test for parameter injection via 'newThemeName' parameter.Check Version:
Check XWiki administration panel or view page source for version informationVerify Fix Applied:
Verify version is 13.10.10, 14.4.6, or 14.9-rc-1+. Test that script injection via 'newThemeName' parameter no longer works.📡 Detection & Monitoring
Log Indicators:
- Unusual requests with 'newThemeName' parameter containing script-like content
- Error logs showing script execution failures
- Unexpected process execution from XWiki context
Network Indicators:
- HTTP requests with 'newThemeName' parameter containing Groovy, Python, or Velocity syntax
- Unusual outbound connections from XWiki server
SIEM Query:
http.url:*newThemeName* AND (http.param:*groovy* OR http.param:*python* OR http.param:*velocity*)🔗 References
- https://github.com/xwiki/xwiki-platform/commit/ea2e615f50a918802fd60b09ec87aa04bc6ea8e2#diff-e2153fa59f9d92ef67b0afbf27984bd17170921a3b558fac227160003d0dfd2aR283-R284
- https://github.com/xwiki/xwiki-platform/security/advisories/GHSA-x2qm-r4wx-8gpg
- https://jira.xwiki.org/browse/XWIKI-19757
- https://github.com/xwiki/xwiki-platform/commit/ea2e615f50a918802fd60b09ec87aa04bc6ea8e2#diff-e2153fa59f9d92ef67b0afbf27984bd17170921a3b558fac227160003d0dfd2aR283-R284
- https://github.com/xwiki/xwiki-platform/security/advisories/GHSA-x2qm-r4wx-8gpg
- https://jira.xwiki.org/browse/XWIKI-19757
