Mezzanine CMS Stored XSS Vulnerability (CVE-2025-6050) Analysis and Fix

Key Information Vulnerability Overview CVE ID: CVE-2025-6050 / CVE-2025-6050 Vulnerability Type: Stored Cross-Site Scripting (XSS) Affected Product: Mezzanine CMS Affected Versions: Versions prior to 6.1.1 Severity: Medium (CVSS Score: 4.8) Vulnerability Details Location: In the function, which fails to properly sanitize blog post titles before including them in a JSON response. Attack Vector: Network Complexity: Low Required Privileges: High (authenticated administrator user required) User Interaction: Required Scope: Changed Confidentiality: Low Integrity: Low Availability: None Timeline Discovery Date: March 15, 2025 Disclosure Date: June 4, 2025 Fix Date: June 4, 2025 Publication Date: June 17, 2025 Impact Authenticated administrator users can execute malicious JavaScript code within another administrator’s browser session. May lead to session hijacking, unauthorized operations, and data leakage. Reproduction Steps 1. Log in to the Mezzanine admin interface. 2. Navigate to “Content” → “Blog Posts”. 3. Create a new blog post containing a malicious JavaScript payload. 4. Save the blog post. 5. Create and edit another blog post. 6. Use the insert/edit links feature, triggering a GET request to . 7. Observe the malicious script executing immediately. 8. Prompt another administrator to click the link. Mitigation Fixed in commit , including proper HTML sanitization. Recommended to upgrade to version 6.1.1. Discoverer Checkmarx AppSec analyst Alex Shleymovich.

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Mezzanine CMS Stored XSS Vulnerability (CVE-2025-6050) Analysis and Fix