CVE-2025-62374 is a prototype pollution vulnerability classified under CWE-1321 affecting the Parse-SDK-JS library used to interact with Parse Server backends from JavaScript applications. The vulnerability exists in versions prior to 7.0.0-alpha.1 and allows attackers to inject malicious payloads that improperly modify object prototype attributes. This manipulation can lead to remote code execution by altering the behavior of JavaScript objects globally within the application context. The affected functions include ParseObject.fromJSON, ParseObject.pin, ParseObject.registerSubclass, and internal components such as ObjectStateMutations and encode/decode, which handle object state and serialization. The vulnerability requires low privileges (PR:L) but no user interaction (UI:N), and can be exploited remotely (AV:N). The CVSS 3.1 score of 6.4 reflects medium severity, primarily due to the potential for confidentiality loss and availability impact, though integrity impact is rated low. No known exploits have been observed in the wild, but the risk remains significant given the widespread use of Parse-SDK-JS in JavaScript applications. The vulnerability is resolved in version 7.0.0, which should be adopted promptly to prevent exploitation.

For European organizations, this vulnerability poses a risk of unauthorized remote code execution within applications using vulnerable versions of Parse-SDK-JS. This can lead to data leakage (confidentiality impact) and service disruption (availability impact), potentially affecting customer data and business operations. Organizations relying on Parse Server backends for critical applications, especially those handling sensitive or regulated data, may face compliance and reputational risks if exploited. The medium CVSS score indicates moderate risk, but the ease of remote exploitation without user interaction increases the threat level. Since the vulnerability affects JavaScript SDKs, web applications and services across various sectors including finance, healthcare, and e-commerce in Europe could be targeted. The lack of known exploits suggests a window for proactive mitigation before widespread attacks occur.

1. Upgrade all instances of Parse-SDK-JS to version 7.0.0 or later immediately to apply the official fix. 2. Conduct a thorough audit of application code to identify and review usage of affected functions such as ParseObject.fromJSON, ParseObject.pin, and ParseObject.registerSubclass. 3. Implement strict input validation and sanitization to prevent injection of malicious payloads that could trigger prototype pollution. 4. Employ runtime application self-protection (RASP) or web application firewalls (WAFs) configured to detect and block suspicious payloads targeting prototype pollution patterns. 5. Monitor application logs for unusual behavior indicative of prototype manipulation or unauthorized code execution attempts. 6. Educate development teams about secure coding practices related to object prototype handling in JavaScript. 7. If upgrading immediately is not feasible, consider isolating vulnerable components and restricting network access to minimize exposure.