scimPatch vulnerable to prototype pollution via unfiltered keys in patch

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

9.1 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:L

EPSS

• CVE-2026-48170: 0.40% estimated exploitation activity in the next 30 days; percentile 34.58 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary scim-patch 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. Impact - Class: Prototype pollution (CWE-1321) - Affected versions: <= 0.9.0 (current HEAD 871b1e2) - Attack vector: Network — sent as part of a normal SCIM PATCH /Users/:id request body. - Privileges required: Whatever the SCIM endpoint requires. For most integrations that's a provisioned IdP, which is "low" in CVSS terms (any authenticated provisioning client). - Scope: Changed — the bug is in a SCIM library but the side effect (Object.prototype mutation) leaks into the entire Node process. Downstream consequences depend on what other code reads from plain…

Published by the source

22 Jun 2026, 22:57 UTC

Last modified by the source

22 Jun 2026, 23:11 UTC

Source last checked

26 Oct 2026, 12:56 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-9m6g-wc8r-q59c

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GHSA-9m6g-wc8r-q59c

3. Revision 1 · created · 23 Oct 2026

   Published from ghsa record GHSA-9m6g-wc8r-q59c

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# Patch Next advisory brief: CVE-2026-48170

Advisory: scimPatch vulnerable to prototype pollution via unfiltered keys in patch
IDs: CVE-2026-48170, GHSA-9m6g-wc8r-q59c
Record: https://patchnext.com/advisories/cve-2026-48170 (revision 3, source checked 26 Oct 2026, 12:56 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: scim-patch 0.9.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm scim-patch: affected <= 0.9.0; fixed in 0.9.1

## Suggested inspection (read-only)
- `npm ls scim-patch --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on scim-patch.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-9m6g-wc8r-q59c (GitHub-reviewed advisory GHSA-9m6g-wc8r-q59c lists affected ranges: npm scim-patch >=0 <=0.9.0)
- Verified: https://osv.dev/vulnerability/GHSA-9m6g-wc8r-q59c (OSV record GHSA-9m6g-wc8r-q59c lists affected ranges: npm scim-patch >=0 <0.9.1 (fixed))

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