---
id: CVE-2026-54737
title: >-
  @phun-ky/defaults-deep is a library like lodash defaultsDeep with array
  preservation and no lodash dependency
summary: >-
  @phun-ky/defaults-deep is a library like lodash defaultsDeep with array
  preservation and no lodash dependency. Prior to 2.0.5, defaultsDeep()
  recursively merges user-supplied objects without filtering proto, constructor,
  and prototype, a…
severity: high
cvss: 7.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L'
cwe:
  - CWE-1321
vendor: phun-ky
product: '@phun-ky/defaults-deep'
affected:
  - '@phun-ky/defaults-deep < 2.0.5'
patched:
  - '@phun-ky/defaults-deep 2.0.5'
published: '2026-07-31'
updated: '2026-09-10'
sourceUpdated: '2026-09-10T20:12:43.783'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-54737'
references:
  - url: >-
      https://github.com/phun-ky/defaults-deep/commit/807dba930f8718f9126cad59d949b8fd3539b059
    label: security-advisories@github.com
  - url: 'https://github.com/phun-ky/defaults-deep/pull/49'
    label: security-advisories@github.com
  - url: 'https://github.com/phun-ky/defaults-deep/releases/tag/2.0.5'
    label: security-advisories@github.com
  - url: >-
      https://github.com/phun-ky/defaults-deep/security/advisories/GHSA-mj3g-7xcc-x4vh
    label: security-advisories@github.com
  - url: 'https://github.com/advisories/GHSA-mj3g-7xcc-x4vh'
tags:
  - nvd
  - ghsa
  - npm
epss: 0.00455
epssPercentile: 0.36834
aliases:
  - GHSA-mj3g-7xcc-x4vh
ecosystem: npm
ingestedAt: '2026-07-31T18:00:26.909Z'
---

## Overview

@phun-ky/defaults-deep is a library like lodash defaultsDeep with array preservation and no lodash dependency. Prior to 2.0.5, defaultsDeep() recursively merges user-supplied objects without filtering proto, constructor, and prototype, allowing properties to be written to Object.prototype. This issue is fixed in version 2.0.5.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-54737)

Affected packages:

- `@phun-ky/defaults-deep < 2.0.5`

Patched in:

- `@phun-ky/defaults-deep 2.0.5`

Source: https://github.com/advisories/GHSA-mj3g-7xcc-x4vh