CVE-2024-14020 identifies a prototype pollution vulnerability in the carboneio carbone library, a NodeJS-based document generation tool. The flaw exists in the Formatter Handler component, specifically within the lib/input.js file, where an attacker can manipulate object prototype attributes improperly. Prototype pollution allows an attacker to modify the base object prototype, potentially altering the behavior of all objects inheriting from it, which can lead to unexpected application behavior or security bypasses. The vulnerability can be exploited remotely without user interaction but requires high complexity due to the need for specific conditions and the prerequisite that the parent NodeJS application also contains the same security flaw. The vulnerability affects a specific commit version (fbcd349077ad0e8748be73eab2a82ea92b6f8a7e) and is fixed in version 3.5.6 by patch 04f9feb24bfca23567706392f9ad2c53bbe4134e. The CVSS 4.0 base score is 2.3, reflecting low severity due to limited impact and difficult exploitability. No public exploits have been reported, indicating a low likelihood of active attacks currently. The vulnerability's impact is primarily on confidentiality, integrity, and availability at a low level, given the limited scope and complexity.

For European organizations using the carboneio carbone library in their NodeJS applications, this vulnerability could allow an attacker to perform prototype pollution attacks, potentially leading to altered application logic or security bypasses. Although the CVSS score is low and exploitation is complex, the impact could be more significant if the parent NodeJS application is also vulnerable, possibly enabling privilege escalation or data manipulation. Organizations relying on automated document generation or formatting services using carbone may face risks of data integrity issues or unexpected application behavior. However, the overall risk is limited due to the high complexity of exploitation and absence of known active exploits. Still, failure to patch could leave systems exposed to future, more sophisticated attacks. The impact on availability is minimal, but integrity and confidentiality could be moderately affected in worst-case scenarios.

European organizations should promptly upgrade the carboneio carbone library to version 3.5.6 or later to apply the official patch (04f9feb24bfca23567706392f9ad2c53bbe4134e). Additionally, review and harden the parent NodeJS applications to ensure they do not contain similar prototype pollution vulnerabilities, as exploitation depends on the parent application's security posture. Implement strict input validation and sanitization in applications using carbone to reduce the risk of malicious input triggering prototype pollution. Employ runtime application self-protection (RASP) or behavior monitoring to detect anomalous prototype modifications. Regularly audit dependencies and monitor for updates or advisories related to carbone and related NodeJS components. Finally, conduct security testing focusing on prototype pollution vectors in development and staging environments before deploying updates.