{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","favicon":"https://feed.craftedsignal.io/favicon-32x32.png","feed_url":"https://feed.craftedsignal.io/cpes/cpe2.3anodejsnode.js/feed.json","home_page_url":"https://feed.craftedsignal.io/","icon":"https://feed.craftedsignal.io/apple-touch-icon.png","items":[{"_cs_actors":[],"_cs_cpes":["cpe:2.3:a:nodejs:node.js:*:*:*:*:*:*:*:*"],"_cs_cves":[],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["Node.js (applications utilizing insecure deepMerge logic)"],"_cs_severities":["medium"],"_cs_tags":["web-application-security","prototype-pollution","nodejs","privilege-escalation"],"_cs_type":"advisory","_cs_vendors":[],"content_html":"\u003cp\u003eCVE-2026-3030 identifies a prototype pollution vulnerability affecting Node.js applications that implement insecure deep merge functions for handling JSON Merge Patch objects. The vulnerability exists when a recursive merge function fails to sanitize input keys, allowing an attacker to pass the \u003ccode\u003e__proto__\u003c/code\u003e key in a JSON request body. By leveraging this, an attacker can modify the prototype of the global Object, injecting or overwriting properties that are subsequently used by the application logic for security checks or control flow. The impact of such pollution can range from unauthorized privilege escalation - such as forcing an application to grant admin rights - to application crashes or, in specific contexts, potential remote code execution. Defenders should review Node.js application code, specifically any custom deep merge utilities that process untrusted user input, to ensure property filtering is implemented.\u003c/p\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eThe vulnerability facilitates privilege escalation and unauthorized access within web applications by manipulating application state through prototype contamination. If successfully exploited, an attacker could bypass authentication mechanisms (e.g., setting \u003ccode\u003eisAdmin\u003c/code\u003e to true in a session object), gain unauthorized administrative access, or trigger denial-of-service conditions.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eAudit codebase for custom \u003ccode\u003edeepMerge\u003c/code\u003e implementations in Node.js applications and implement robust input sanitization to block keys named \u003ccode\u003e__proto__\u003c/code\u003e, \u003ccode\u003econstructor\u003c/code\u003e, or \u003ccode\u003eprototype\u003c/code\u003e.\u003c/li\u003e\n\u003cli\u003eEnsure that all JSON parsing and merging logic in web APIs explicitly validates incoming keys against a blocklist of sensitive prototype identifiers.\u003c/li\u003e\n\u003cli\u003eUtilize security scanning tools capable of identifying prototype pollution patterns in custom application logic.\u003c/li\u003e\n\u003cli\u003eMonitor web application logs for suspicious \u003ccode\u003ePATCH\u003c/code\u003e requests containing \u003ccode\u003e__proto__\u003c/code\u003e keys in the request body.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-09-07T21:43:28Z","date_published":"2026-09-07T21:43:28Z","id":"https://feed.craftedsignal.io/briefs/2026-09-cve-2026-3030-prototype-pollution/","summary":"A prototype pollution vulnerability, tracked as CVE-2026-3030, allows attackers to inject malicious properties into the global Object.prototype via insecure deep merge functions, potentially leading to privilege escalation.","title":"Prototype Pollution Vulnerability in Node.js JSON Merge Patch Implementations","url":"https://feed.craftedsignal.io/briefs/2026-09-cve-2026-3030-prototype-pollution/"}],"language":"en","title":"CraftedSignal Threat Feed - Cpe:2.3:a:nodejs:node.js:*:*:*:*:*:*:*:*","version":"https://jsonfeed.org/version/1.1"}