CVE-2025-49579: 
PHP vulnerability analysis and mitigation

CVE-2025-49579 affects the Citizen MediaWiki skin, a component that makes extensions part of a cohesive experience. The vulnerability was discovered and disclosed on June 11, 2025, and involves a stored Cross-Site Scripting (XSS) vulnerability in menu headings. The issue affects all system messages in menu headings using the Menu.mustache template, where raw HTML can be inserted into the DOM by users with specific permissions (GitHub Advisory).

The vulnerability exists in the Menu.mustache template implementation where system messages for menu headings are inserted unescaped into raw HTML. The issue has been assigned a CVSS v3.1 base score of 6.5 (Medium) with the vector string CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N. The vulnerability is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation) and CWE-80 (GitHub Advisory, Wiz).

The vulnerability impacts wikis where a user group has the 'editinterface' permission but not the 'editsitejs' user right. When exploited, it allows attackers to insert arbitrary HTML into the DOM through menu headings, potentially leading to stored cross-site scripting attacks. This could result in unauthorized access to sensitive information and potential manipulation of web content (GitHub Advisory).

The vulnerability has been patched in version 3.3.1. The fix involves proper escaping of menu headings and system messages. The patch is available in commit 93c36ac778397e0e7c46cf7adb1e5d848265f1bd, which addresses various stored XSS system message vulnerabilities (Wiz).