Vulnerability library
Security checkJuly 14, 2026

Prototype pollution in @feathersjs/commons _.merge via JSON-parsed __proto__

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Description

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__ (or constructor / prototype) key, that key is returned as an own-enumerable property.

Recommendation

Update the @feathersjs/commons package to the latest compatible version. Followings are version details:

  • Affected version(s): <= 5.0.44
  • Patched version(s): 5.0.45

References

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Related Issues

See something that needs correcting? Let us knowUpdated July 14, 2026