Ameeba Security Research

Defensive CVE and exploit intelligence

Ameeba Blog Search
TRENDING · 1 WEEK
Attack Vector
Vendor
Severity

CVE-2025-53836: Critical Vulnerability in XWiki Rendering System

Views: 817

Overview

This blog post examines the critical vulnerability, CVE-2025-53836, identified in XWiki Rendering, a generic system used for converting various syntaxes. This vulnerability poses a serious threat due to its severity and potential impact, which includes system compromise and data leakage. It affects XWiki versions starting from 4.2-milestone-1 and prior to versions 13.10.11, 14.4.7, and 14.10. As such, any organization or user employing these versions of XWiki is at risk and should take immediate actions to mitigate this vulnerability.

Vulnerability Summary

CVE ID: CVE-2025-53836
Severity: Critical (CVSS: 9.9)
Attack Vector: Network
Privileges Required: Low
User Interaction: Required
Impact: Potential system compromise or data leakage

Affected Products

Ameeba Chat Icon Share secrets securely

Ameeba is private infrastructure for communication and sensitive work built on encrypted identity instead of exposed corporate identity systems.

Passwords, credentials, confidential files, screenshots, internal discussions, sensitive AI context, and private coordination should not become exposed across ordinary communication platforms.

  • • Encrypted identity
  • • Private Spaces for organizations and teams
  • • End-to-end encrypted chat, calls, files, and notes
  • • Sensitive AI work and protected collaboration
  • • Built for information that cannot leak

Our mission is to secure human work alongside AI.

Product | Affected Versions

XWiki | 4.2-milestone-1 to 13.10.10
XWiki | 4.2-milestone-1 to 14.4.6
XWiki | 4.2-milestone-1 to 14.9

How the Exploit Works

The vulnerability lies in the default macro content parser of XWiki Rendering system. When executing nested macros, it fails to preserve the restricted attribute of the transformation context. This lapse allows the execution of macros that are typically forbidden in restricted mode, including script macros. Particularly, the cache and chart macros that are bundled in XWiki can exploit this vulnerability. This flaw in the parser creates a potential pathway for unauthorized code execution, leading to system compromise or data leakage.

Conceptual Example Code

The following conceptual example provides an insight into how the vulnerability might be exploited. This could be a possible HTTP request exploiting the vulnerability:

POST /XWiki/RenderMacro HTTP/1.1
Host: target.example.com
Content-Type: application/x-www-form-urlencoded
macro_name=script&macro_content=<script>malicious_code_here</script>

In the above example, an attacker could potentially embed malicious code within the script macro, which gets executed due to the parser’s inability to enforce restrictions.

Mitigation Guidance

Users are urged to apply the patch provided by the vendor for XWiki versions 13.10.11, 14.4.7 and 14.10. As an interim mitigation measure, users could use a Web Application Firewall (WAF) or Intrusion Detection System (IDS) to monitor and block malicious traffic. Furthermore, to avoid the exploitation of this bug, it is recommended to disable comments for untrusted users until the system is upgraded to a patched version. It is important to note that users with edit rights will still be able to add comments via the object editor even if comments have been disabled.

Want to discuss this further? Join the Ameeba Cybersecurity Group Chat.

Disclaimer:

The information and code presented in this article are provided for educational and defensive cybersecurity purposes only. Any conceptual or pseudocode examples are simplified representations intended to raise awareness and promote secure development and system configuration practices.

Do not use this information to attempt unauthorized access or exploit vulnerabilities on systems that you do not own or have explicit permission to test.

Ameeba and its authors do not endorse or condone malicious behavior and are not responsible for misuse of the content. Always follow ethical hacking guidelines, responsible disclosure practices, and local laws.

More posts

Ameeba Chat