CVE-2024-1791 in CodeMirror Blocks Plugin
Summary
by MITRE • 02/28/2024
The CodeMirror Blocks plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the Code Mirror block in all versions up to, and including, 1.2.4 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
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Analysis
by VulDB Data Team • 03/04/2025
The CodeMirror Blocks plugin for WordPress represents a significant security vulnerability classified as CVE-2024-1791, affecting all versions up to and including 1.2.4. This vulnerability manifests as a stored cross-site scripting flaw within the Code Mirror block functionality, creating a persistent threat vector that can compromise user sessions and execute malicious code within the context of affected websites. The vulnerability specifically targets the plugin's handling of user input within the code editing interface, where insufficient sanitization and output escaping mechanisms fail to properly validate or encode potentially malicious content submitted by authenticated users.
The technical flaw stems from inadequate input validation processes within the plugin's code processing pipeline, where user-supplied content entered through the Code Mirror block is not adequately sanitized before being stored in the WordPress database. This allows malicious actors to inject script tags or other malicious payloads that persist in the system and execute whenever affected pages are rendered. The vulnerability operates at the intersection of improper input validation and output encoding failures, creating a condition where user-generated content containing malicious scripts is stored and later executed without proper context-aware escaping. This issue aligns with CWE-79, which specifically addresses cross-site scripting vulnerabilities resulting from insufficient output escaping and improper input validation.
The operational impact of this vulnerability is particularly concerning given that it requires only contributor-level access or higher to exploit, making it accessible to users who already possess significant privileges within WordPress installations. Authenticated attackers can leverage this vulnerability to inject malicious scripts that will execute in the browsers of other users who access pages containing the compromised content. This creates a persistent threat that can compromise user sessions, steal cookies, redirect users to malicious sites, or perform actions on behalf of authenticated users. The stored nature of the vulnerability means that once exploited, the malicious payloads remain active until manually removed from the database, potentially affecting multiple users over extended periods.
Security professionals should prioritize immediate remediation of this vulnerability through plugin updates to versions that address the input sanitization and output escaping deficiencies. The recommended mitigation strategy includes implementing proper content validation mechanisms that filter and sanitize all user input before storage, combined with context-appropriate output encoding to prevent script execution in different rendering contexts. Organizations should also consider implementing additional security controls such as web application firewalls, input validation rules, and regular security audits of plugin installations to prevent similar vulnerabilities from emerging in other components of their WordPress environments. This vulnerability demonstrates the critical importance of maintaining up-to-date software components and implementing comprehensive security practices to protect against persistent threats in content management systems.
The attack surface for this vulnerability extends beyond simple script injection to include potential privilege escalation and session hijacking scenarios, particularly when combined with other security weaknesses in WordPress installations. From an att&ck framework perspective, this vulnerability maps to techniques involving code injection and credential access, potentially enabling attackers to establish persistent access to compromised systems. The vulnerability also highlights the importance of principle of least privilege implementation, as the ability to inject malicious code through a contributor account represents a significant escalation opportunity for attackers seeking to gain broader system access. Regular security assessments and proper input/output handling practices remain essential defensive measures against such vulnerabilities in web applications.