CVE-2026-55091 flat-to-nested: Prototype pollution in flat-to-nested convert() via __proto__ parent/id key

flat-to-nested converts a hierarchy from a flat representation to a nested representation. Prior to 1.1.2, FlatToNested.prototype.convert in index.js uses attacker-influenced id and parent record fields directly as keys in the plain temp and pendingChildOf objects. When parent or id is proto,...