GHSA-xgh5-w62m-8mpr CI4MS: Menu Management (Posts) Full Account Takeover for All-Roles & Privilege-Escalation via Stored DOM XSS

• Packagist ci4-cms-erp/ci4ms: < 0.31.0.0 → fixed in 0.31.0.0

Summary Vulnerability: Stored DOM XSS via Posts Added to Menu (Persistent Payload Injection) • Stored Cross-Site Scripting via Unsafe Rendering of Post Entries in Menu Management Description The application fails to properly sanitize user-controlled input when adding Posts to navigation menus through the Menu Management functionality. Post-related data selected via the Posts section is stored server-side and rendered without proper output encoding. These stored values are later rendered unsafely within administrative dashboards and public-facing navigation menus, resulting in stored DOM-based cross-site scripting (XSS). Affected Functionality • Menu Management – Posts section • Adding posts to navigation menus • Menu storage and rendering logic Attack Scenario • An attacker creates or controls a post containing a malicious JavaScript payload. • The attacker adds the post to the menu using the Posts functionality in Menu Manager. • The application stores the menu entry without sanitization or encoding. • The payload persists and executes whenever the menu is rendered. Impact • Persistent Stored DOM XSS • Execution of arbitrary JavaScript in victims’ browsers • Privilege escalation in administrative contexts • Full administrator account takeover • Full account takeover across all roles • Full compromise of the entire application via global navigation execution Endpoint: • `/backend/menu/` Steps To Reproduce (POC) 1. Navigate to Menu Management 2. Use the Posts section to add a post containing an XSS payload such as: `` 3. Save the menu 4. View the menu in the administrative panel or any public-facing page 5. Observe the JavaScript payload executing automatically Remediation • Avoid unsafe DOM manipulation methods: Do not use `.html()`, `innerHTML`, or similar sink functions in client-side JavaScript or server-side templating (e.g., PHP). Even when user input flowing into these sinks is not immediately apparent, they can introduce Cross-Site Scripting (XSS) vulnerabilities that an attacker may exploit. • Apply output encoding: Implement HTML entity encoding on all user-controlled data before rendering it in the browser. This helps neutralize potentially malicious input. • Implement input sanitization: Ensure that all user-supplied input is properly sanitized before processing or output. Currently, no sanitization mechanisms are in place, which should be addressed as a priority. • Enforce security headers and cookie attributes: • Content Security Policy (CSP): Define and enforce a strict CSP to limit the execution of unauthorized scripts. • HttpOnly flag: Set the `HttpOnly` attribute on session cookies to prevent client-side script access. • SameSite attribute: Configure the `SameSite` cookie attribute to mitigate Cross-Site Request Forgery (CSRF) risks. • Secure flag: Ensure all cookies are transmitted only over HTTPS by enabling the `Secure` attribute. These measures collectively reduce the impact of XSS and help prevent escalation paths such as CSRF via XSS. Ready Video POC: https://mega.nz/file/PcMiUA5K#L2RlZJa340Q8K42TksxiXMuo_9XsRYPi14-WvBnak2A