Summary
@nevware21/ts-utils: Prototype Pollution in objDeepCopy/objCopyProps via for...in without hasOwnProperty
The _copyProps function in lib/src/object/copy.ts uses for...in to iterate over source object properties without an Object.hasOwnProperty check, and does not filter dangerous keys (proto, constructor, prototype). This allows an attacker to pollute the prototype chain of all objects in the application.
Details
In _copyProps() (copy.ts lines 186-191), the code iterates all enumerable properties including inherited ones and dangerous keys like proto. Any object with a proto key (e.g., from untrusted JSON input) will overwrite the target's prototype.
PoC
const malicious = JSON.parse('{"__proto__": {"polluted": true}}');
objDeepCopy(malicious);
console.log({}.polluted); // true
Impact
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Add objHasOwnProperty check and filter proto, constructor, prototype keys.
Frequently Asked Questions
- What is CVE-2026-46681? CVE-2026-46681 is a high-severity security vulnerability in @nevware21/ts-utils (npm), affecting versions <= 0.13.0. It is fixed in 0.14.0.
- Which versions of @nevware21/ts-utils are affected by CVE-2026-46681? @nevware21/ts-utils (npm) versions <= 0.13.0 is affected.
- Is there a fix for CVE-2026-46681? Yes. CVE-2026-46681 is fixed in 0.14.0. Upgrade to this version or later.
- Is CVE-2026-46681 exploitable, and should I be worried? Whether CVE-2026-46681 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-46681 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-46681? Upgrade
@nevware21/ts-utilsto 0.14.0 or later.