CVE-2021-24643 in WP Map Block Plugin
Summary
by MITRE • 09/28/2021
The WP Map Block WordPress plugin before 1.2.3 does not escape some attributes of the WP Map Block, which could allow users with a role as low as contributor to perform Stored Cross-Site Scripting attacks
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Analysis
by VulDB Data Team • 10/03/2021
The WP Map Block WordPress plugin vulnerability CVE-2021-24643 represents a critical stored cross-site scripting flaw that affects versions prior to 1.2.3. This vulnerability exists within the plugin's handling of user input attributes, specifically failing to properly escape or sanitize data that is stored and subsequently rendered on web pages. The issue is particularly concerning because it allows users with minimal privileges, including contributors who typically have limited capabilities within WordPress environments, to execute malicious scripts. The vulnerability stems from improper output escaping mechanisms that fail to neutralize potentially harmful HTML or JavaScript content when the map block attributes are processed and stored in the database.
The technical implementation of this vulnerability occurs when the plugin processes map block attributes that users can input through the WordPress editor interface. Contributors and other low-privilege users can insert malicious script code into these attributes, which are then stored in the WordPress database without proper sanitization. When other users view pages containing these map blocks, the stored malicious code executes in their browsers, potentially leading to session hijacking, credential theft, or other malicious activities. This represents a classic stored XSS vulnerability where the malicious payload is permanently stored on the server and executed whenever the affected content is retrieved. The vulnerability aligns with CWE-79 which describes improper neutralization of input during web page generation, specifically in the context of stored cross-site scripting attacks.
The operational impact of this vulnerability extends beyond simple script execution as it can enable attackers to escalate their privileges within the WordPress environment. Once a contributor gains the ability to execute arbitrary JavaScript code through the map block functionality, they can potentially access other user sessions, modify content, or even gain administrative access if the environment lacks proper security controls. The attack vector is particularly dangerous because it requires minimal user interaction beyond creating a map block with malicious content, making it an attractive target for automated exploitation. This vulnerability can also be leveraged to deliver malware payloads or redirect users to phishing sites, creating a broader security threat beyond the immediate WordPress installation.
Organizations should immediately upgrade to WP Map Block version 1.2.3 or later to remediate this vulnerability, as no effective workarounds exist for the core escaping issue. The recommended mitigation strategy involves implementing comprehensive input validation and output escaping mechanisms for all user-supplied content, particularly in plugins that handle rich text or map data. Security teams should also consider implementing web application firewalls with XSS detection capabilities and monitoring for suspicious map block creation activities. Additionally, regular security audits of WordPress plugins should be conducted to identify similar vulnerabilities, and user privilege management should be strictly enforced to limit contributor capabilities where possible. This vulnerability demonstrates the importance of proper input sanitization and output escaping practices, aligning with ATT&CK technique T1213 which covers data from information repositories and the broader category of web application attacks that leverage improper input handling.