fix(nested-obj): guard against prototype pollution in path traversal#82
Merged
pyramation merged 1 commit intomainfrom May 9, 2026
Merged
fix(nested-obj): guard against prototype pollution in path traversal#82pyramation merged 1 commit intomainfrom
pyramation merged 1 commit intomainfrom
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Reject unsafe path segments (__proto__, constructor, prototype) in get, set, and has methods to prevent prototype pollution attacks. Extracts path parsing into a shared parsePath helper that validates all segments before traversal. CWE-1321 / CVSS 3.1 8.2 High
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Summary
Fixes a prototype pollution vulnerability (CWE-1321) in
nested-obj. Theset,get, andhasmethods walked dot-notation paths without filtering unsafe keys, allowingset(obj, '__proto__.x', value)to write toObject.prototype.The fix extracts path parsing into a shared
parsePathhelper that rejects__proto__,constructor, andprototypesegments with a thrown error before any property traversal occurs. Six new tests verify the guard across all three methods.