CVE-2022-39287 is a vulnerability affecting the Node.js middleware 'tiny-csrf', which is designed to provide protection against Cross-Site Request Forgery (CSRF) attacks. The issue exists in versions prior to 1.1.0, where the middleware transmits CSRF tokens via cookies that are not encrypted. This results in the cleartext transmission of sensitive information (the CSRF tokens), violating secure communication principles and exposing the tokens to interception by network attackers. The vulnerability is classified under CWE-319, which concerns the cleartext transmission of sensitive information. Since CSRF tokens are intended to be secret and used to validate legitimate user requests, their exposure can allow attackers to bypass CSRF protections by capturing and reusing these tokens. The vulnerability was addressed in commit '8eead6d' and fixed in version 1.1.0 of tiny-csrf. No known workarounds exist, so upgrading is the primary remediation. There are no known exploits in the wild as of the published date (October 7, 2022). The vulnerability does not require user interaction beyond normal web browsing and does not require authentication to exploit, as the tokens are transmitted in cleartext and can be intercepted by a man-in-the-middle or network attacker. The scope is limited to applications using the affected versions of tiny-csrf middleware, which is a niche but critical component for CSRF protection in Node.js web applications. The vulnerability impacts the confidentiality of CSRF tokens, potentially undermining the integrity of web session protections and enabling unauthorized actions on behalf of users.

For European organizations, the impact of this vulnerability depends largely on the adoption of the tiny-csrf middleware in their web applications. Organizations using affected versions (<1.1.0) risk exposure of CSRF tokens, which can lead to successful CSRF attacks. This can result in unauthorized actions performed on behalf of authenticated users, potentially leading to data manipulation, unauthorized transactions, or privilege escalation within web applications. Sectors with high reliance on web applications for critical services—such as finance, healthcare, government, and e-commerce—are particularly at risk. The vulnerability could undermine trust in web services, cause data breaches, and lead to regulatory non-compliance under GDPR due to inadequate protection of user data. Although no exploits are currently known in the wild, the ease of intercepting unencrypted cookies over insecure networks (e.g., public Wi-Fi) increases the risk of exploitation. The impact on availability is minimal, but the confidentiality and integrity of user sessions are at risk. Organizations with remote or mobile workforces using vulnerable applications are more exposed due to increased likelihood of network interception.

The primary and only effective mitigation is to upgrade tiny-csrf to version 1.1.0 or later, where cookies are encrypted and CSRF tokens are no longer transmitted in cleartext. Organizations should audit their Node.js applications to identify usage of tiny-csrf and verify the version in use. If upgrading is not immediately possible, organizations should enforce strict transport layer security by ensuring all web traffic uses HTTPS with HSTS enabled to prevent interception. Additionally, network segmentation and VPN use can reduce exposure to network-based attackers. Application developers should consider implementing additional CSRF protections such as double-submit cookies or SameSite cookie attributes to complement the middleware. Monitoring network traffic for unencrypted CSRF tokens and anomalous requests can help detect exploitation attempts. Finally, organizations should educate developers on secure cookie handling and regularly update dependencies to avoid similar vulnerabilities.