Description
A prototype pollution vulnerability exists in @phun-ky/defaults-deep prior to version 2.0.5.
The library recursively merged user-supplied objects without filtering unsafe property names such as __proto__, constructor, and prototype. An attacker able to supply crafted input could cause properties to be written to Object.prototype, resulting in prototype pollution affecting all objects within the running process.
Recommendation
Update the @phun-ky/defaults-deep package to the latest compatible version. Followings are version details:
- Affected version(s): < 2.0.5
- Patched version(s): 2.0.5
References
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See something that needs correcting? Let us knowUpdated July 31, 2026