Skip to content
OpenAdvisories
High · 8.2 CVE-2026-104852 EUVD-2026-92849GHSA-7mx3-vvmw-hjmv

GraphQL Tools has prototype pollution in well-established utility function `mergeDeep`

Published Oct 5, 2026 · Updated Oct 6, 2026 · Assigned by GitHub_M

Description

GraphQL Tools provides utilities for building, stitching, and mocking GraphQL schemas. Prior to 12.0.1, the GraphQL Tools utils package's mergeDeep function follows inherited properties while recursively merging source objects and does not exclude __proto__, constructor, or prototype keys. An unauthenticated GraphQL client can alias fields to those names so responses from two subgraphs collide during ordinary supergraph result merging, causing mergeDeep to traverse Object and Function prototypes and overwrite Function.prototype.call with a subgraph-supplied value. This breaks subsequent requests in the process until restart. This issue is fixed in version 12.0.1.

Affected products

VendorProductAffectedFixed
ardatan graphql-tools < 12.0.1 —

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

Wolfi

ReleasePackageFixed inAdvisory
Wolfi rolling langfuse-3-worker 3.225.11-r9 —

Affected packages

EcosystemPackageAffectedFixedRecord
npm @graphql-tools/utils < 12.0.1 12.0.1 GHSA-7mx3-vvmw-hjmv

References