@phun-ky/defaults-deep Has a Prototype Pollution issue via Unsafe Recursive Property Merging

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

• GHSA-mj3g-7xcc-x4vh
• CVE-2026-54737
• CWE-1321
• CAPEC-310
• OWASP 2021-A6

Related Issues

• @rvf/set-get has a prototype pollution issue that's reachable via @rvf/core preprocessFormData (HTTP form data) - CVE-2026-44483
• axios has DoS & Header Injection via Prototype Pollution Read-Side Gadgets in axios merge functions - CVE-2026-44490
• Axios has a Patch Bypass: Proxy-Authorization Header Injection via Prototype Pollution — Incomplete Null-Prototype Fix - CVE-2026-44489
• Jodit has prototype pollution via Jodit.configure() / ConfigMerge - CVE-2026-54756

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Tags:

npm

@phun-ky/defaults-deep