MediumCVSS 6.5/10Version 3.1IDORPublicCVE-2026-28217

Public February 2026

Hoppscotch GraphQL Collection Lookup Leaked Other Users’ Secrets

BugBunny.ai discovered an IDOR in Hoppscotch’s userCollection GraphQL query. Any authenticated user could request another user’s collection by ID and receive serialized request definitions that often contained API keys, bearer tokens, and other private data.

TL;DR

Impact

Authenticated users can read other users’ private API collections and the secrets stored inside them.

Vector

GraphQL userCollection queries using another user’s collection ID.

Surface

Hoppscotch self-hosted backend releases up to 2026.1.1.

Status

Published and fixed in Hoppscotch 2026.2.0.

Root Cause

The userCollection resolver accepted a collection ID and called a service method that performed a raw lookup by that ID. Unlike neighboring operations, it never injected the authenticated user or applied the existing ownership check before returning the record.

Because the returned object included serialized request data, the issue exposed more than titles or metadata. It leaked complete collections, authorization headers, bearer tokens, and enough structure to traverse parent and child collections across the victim’s workspace.

Product

Hoppscotch

Affected

<= 2026.1.1

Patched

2026.2.0

Weaknesses

CWE-639: Authorization Bypass Through User-Controlled Key (IDOR)

Mitigation

  • Upgrade Hoppscotch to version 2026.2.0 or later.
  • Require ownership validation in the resolver or service layer before returning any collection data.
  • Review related field resolvers such as parent and children accessors for consistent authorization checks.

Credits & Disclosure

Published via GitHub Security Advisory GHSA-m5pg-r4jp-qq75 after coordinated disclosure with the Hoppscotch maintainers.

CVE-2026-28217HoppscotchPublic
CVE-2026-28217: Hoppscotch GraphQL Collection Lookup Leaked Other Users’ Secrets | BugBunny.ai | BugBunny.ai