CVE WatchJul 17, 2026

CVE-2026-54335

Feathersjs is a framework for creating web APIs and real-time applications with TypeScript or JavaScript. In 5.0.44 and earlier, the _.merge

CVSS

3.7

Low

EPSS

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KEV

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Exploit Today

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0-100

Published: Jul 17, 2026 · Last modified: Jul 17, 2026 · CWE-1321

EPSS · 30d

Not enough EPSS history yet.

Technical description

Feathersjs is a framework for creating web APIs and real-time applications with TypeScript or JavaScript. In 5.0.44 and earlier, the _.merge(target, source) utility exported by @feathersjs/commons recursively merges source into target by iterating Object.keys(source). When source was produced by JSON.parse and contains a __proto__, constructor, or prototype key, that key is returned as an own-enumerable property; the recursive merge then resolves target['__proto__'] to Object.prototype and writes attacker-supplied properties onto it, polluting the prototype for all plain objects in the process for the lifetime of the Node process. This issue is fixed in version 5.0.45.

Official references

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