---
id: CVE-2026-48170
title: >-
  `scim-patch`, a library to perform SCIM patch, prior to version 0.9.1 performs
  prototype pollution when applying a SCIM PATCH operation whose `value` object
  contains a key like `"__proto__.someProp"`
summary: >-
  `scim-patch`, a library to perform SCIM patch, prior to version 0.9.1 performs
  prototype pollution when applying a SCIM PATCH operation whose `value` object
  contains a key like `"__proto__.someProp"`. After one such patch,

  `Object.protot…
severity: critical
cvss: 9.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:L'
cwe:
  - CWE-1321
vendor: scim-patch
product: scim-patch
affected:
  - scim-patch <= 0.9.0
patched:
  - scim-patch 0.9.1
published: '2026-08-07'
updated: '2026-09-18'
sourceUpdated: '2026-09-18T20:09:01.757'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-48170'
references:
  - url: >-
      https://github.com/thomaspoignant/scim-patch/commit/260f9cd2ac5ceac3976978850bb47dcb391720f6
    label: security-advisories@github.com
  - url: >-
      https://github.com/thomaspoignant/scim-patch/security/advisories/GHSA-9m6g-wc8r-q59c
    label: security-advisories@github.com
  - url: >-
      https://github.com/thomaspoignant/scim-patch/security/advisories/GHSA-9m6g-wc8r-q59c
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
  - url: 'https://github.com/advisories/GHSA-9m6g-wc8r-q59c'
tags:
  - nvd
  - ghsa
  - npm
epss: 0.00307
epssPercentile: 0.2365
ecosystem: npm
ingestedAt: '2026-06-29T13:24:35.494Z'
---

## Overview

`scim-patch`, a library to perform SCIM patch, prior to version 0.9.1 performs prototype pollution when applying a SCIM PATCH operation whose `value` object contains a key like `"__proto__.someProp"`. After one such patch,
`Object.prototype.someProp` is set process-wide, affecting every plain object in the Node process. Any service that calls `scimPatch()` on attacker-controlled JSON (i.e. any SCIM endpoint accepting `PATCH` from an external IdP) is exploitable on a stock Node runtime. Version 0.9.1 contains a patch. A workaround is available. Calling `Object.freeze(Object.prototype)` (and the same on `Array.prototype`, `Function.prototype`) at process startup neutralizes this class of bug — assignment to a frozen prototype becomes a silent no-op in sloppy mode or a `TypeError` in strict mode. Node's `--frozen-intrinsics` flag does this for built-ins automatically.

## Remediation

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

## Package advisory (CVE-2026-48170)

Affected packages:

- `scim-patch <= 0.9.0`

Patched in:

- `scim-patch 0.9.1`

Source: https://github.com/advisories/GHSA-9m6g-wc8r-q59c