Skip to content
Patch Next
Sign inAdd to your agent

← Actionable
High, CVSS 8.7amended

Grackle: Fail-open authorization in the MCP tool layer lets scoped agents perform cross-task and cross-session mutations (IDOR)

GHSA-f9ff-5x35-7gfw

What to do

Vendor response not established. Follow the primary source's mitigation guidance and check back for a fix.

This page has no inventory attached, so it cannot say whether you are affected. A vendor fix is not proof that your deployment is fixed.

Add to your agent

Affected packages

  • npm @grackle-ai/auth

    Affected
    <= 0.132.1
    Fixed in
    no fixed version recorded

  • npm @grackle-ai/plugin-core

    Affected
    <= 0.132.1
    Fixed in
    no fixed version recorded

  • npm @grackle-ai/mcp

    Affected
    <= 0.132.1
    Fixed in
    no fixed version recorded

Sources

Severity and exploitation
Exploitation
No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.
CVSS 4.0
8.7 · CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N · score source
EPSS
No dated EPSS signal available.
Source description

As published by the source; long descriptions are shortened.

Summary Authorization for scoped (agent) MCP callers is enforced inline, per tool, and is applied inconsistently — several mutating tools silently omit the ancestry/workspace check that their siblings perform. Because the MCP server authenticates all outbound gRPC with the full server API key and the backend gRPC handlers perform no caller-based authorization, the MCP tool layer is the sole authorization boundary. A malicious or prompt-injected scoped agent can therefore perform cross-task and cross-session operations it should not be allowed to (an IDOR / privilege-boundary bypass). This advisory bundles the audit's Systemic Pattern A findings: F2, F6, F7, F12 (and the duplicate F19). Affected versions @grackle-ai/mcp (with @grackle-ai/plugin-core / @grackle-ai/auth) at 0.132.1 and earlier. Root cause - mcp-server.ts:111-127 (createGrpcClients) sets Authorization: Bearer ${apiKey} (the full server key) on every outbound gRPC call. - Backend handlers (updateTask, deleteTask,…

Dates and revisions
Published by the source
Last modified by the source
Source last checked
  1. Revision 3 · amended ·

    Amended from ghsa record GHSA-f9ff-5x35-7gfw

  2. Revision 2 · amended ·

    Reviewed OSV alias/range/CVSS4 correction; package source scopes and original publication preserved. No customer finding resolved.

  3. Revision 1 · created ·

    Published from osv record GHSA-f9ff-5x35-7gfw

Agent brief

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: GHSA-f9ff-5x35-7gfw

Advisory: Grackle: Fail-open authorization in the MCP tool layer lets scoped agents perform cross-task and cross-session mutations (IDOR)
IDs: GHSA-f9ff-5x35-7gfw
Record: https://patchnext.com/advisories/ghsa-f9ff-5x35-7gfw (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: High (CVSS 8.7)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor response not established. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm @grackle-ai/auth: affected <= 0.132.1
- npm @grackle-ai/plugin-core: affected <= 0.132.1
- npm @grackle-ai/mcp: affected <= 0.132.1

## Suggested inspection (read-only)
- `npm ls @grackle-ai/auth --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.
- `npm ls @grackle-ai/plugin-core --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.
- `npm ls @grackle-ai/mcp --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on @grackle-ai/auth, @grackle-ai/plugin-core, @grackle-ai/mcp.
- 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://osv.dev/vulnerability/GHSA-f9ff-5x35-7gfw (OSV record GHSA-f9ff-5x35-7gfw lists affected ranges: npm @grackle-ai/mcp >=0 =0 =0 <=0.132.1)
- Verified: https://github.com/advisories/GHSA-f9ff-5x35-7gfw (GitHub-reviewed advisory GHSA-f9ff-5x35-7gfw lists affected ranges: npm @grackle-ai/mcp >=0 =0 =0 <=0.132.1)

Commands are suggestions: review each one before running it.

Loading voting…