CVE-2023-46809 is a high-severity vulnerability affecting Node.js versions 4.0 through 21.0 that bundle or dynamically link to an unpatched version of OpenSSL. The vulnerability arises from the allowance of PKCS #1 v1.5 padding during RSA decryption operations using a private key. This enables exploitation via the so-called Marvin Attack, a cryptographic attack that targets RSA implementations vulnerable to padding oracle attacks. Specifically, if an attacker can submit crafted ciphertexts to a vulnerable Node.js instance, they may be able to decrypt sensitive data or recover private keys without authorization. The vulnerability is rooted in improper handling of RSA decryption padding, classified under CWE-385 (Use of Privileged Instruction Without Authorization), indicating that unauthorized cryptographic operations can be performed. The CVSS v3.1 base score is 7.4, reflecting a high impact on confidentiality and integrity, with no impact on availability. The attack vector is network-based (AV:N), requires high attack complexity (AC:H), no privileges (PR:N), and no user interaction (UI:N). The vulnerability scope is unchanged (S:U), meaning the impact is limited to the vulnerable component. No known exploits in the wild have been reported yet. The vulnerability affects a broad range of Node.js versions, which are widely used in server-side JavaScript applications, including web servers, APIs, and microservices, making this a significant concern for organizations relying on Node.js for critical infrastructure.

For European organizations, the impact of CVE-2023-46809 can be substantial due to the widespread adoption of Node.js in enterprise environments, including financial services, healthcare, government, and technology sectors. Exploitation could lead to unauthorized decryption of sensitive data, exposure of private keys, and compromise of cryptographic operations, undermining the confidentiality and integrity of communications and stored data. This could result in data breaches, intellectual property theft, and loss of trust from customers and partners. Given the high attack complexity, exploitation may require sophisticated capabilities, but the lack of required privileges or user interaction lowers the barrier for remote attackers. Organizations running Node.js applications that perform RSA decryption using private keys with PKCS #1 v1.5 padding are particularly at risk. The vulnerability could also affect cloud services and SaaS providers based in Europe that use Node.js, potentially impacting a large number of downstream customers. Compliance with GDPR and other data protection regulations means that any data compromise could lead to significant legal and financial penalties.

European organizations should immediately audit their Node.js environments to identify versions between 4.0 and 21.0 that bundle or dynamically link to OpenSSL versions vulnerable to the Marvin Attack. Specific mitigation steps include: 1) Upgrading Node.js to versions that include patched OpenSSL libraries or applying patches to OpenSSL independently if dynamically linked. 2) Disabling or avoiding the use of PKCS #1 v1.5 padding for RSA decryption in favor of more secure padding schemes like OAEP where possible. 3) Implementing strict cryptographic hygiene by enforcing the use of up-to-date cryptographic libraries and configurations. 4) Conducting code reviews and penetration testing focused on cryptographic operations to detect potential misuse or exposure. 5) Monitoring network traffic and application logs for anomalous decryption requests that could indicate exploitation attempts. 6) Employing runtime application self-protection (RASP) or Web Application Firewalls (WAF) with rules to detect and block suspicious cryptographic operations. 7) Coordinating with software vendors and cloud providers to ensure timely patching and updates. These steps go beyond generic advice by focusing on cryptographic configuration and operational monitoring specific to this vulnerability.