---
id: "CVE-2026-110279"
page: "https://infrastack.ai/live/CVE-2026-110279"
kind: "vulnerability"
aliases: ["CVE-2026-110279"]
title: "IBM ContextForge MCP Gateway: header overrides upstream credentials, bypassing per-user permissions"
severity: "high"
cvss: 8.1
epss: null
exploited: false
status: "open"
category: "ai-tooling"
products: [{"name": "IBM ContextForge MCP Gateway", "fixed": ["1.1.1"], "affected": ">= 1.0.0, <= 1.1.0", "ecosystem": "vendor"}]
ecosystems: []
tags: ["ai-tooling", "ibm-contextforge", "mcp", "self-hosted"]
not_affected_if: ["no-upstream-auth-configured", "outside-affected-range"]
published_at: "2026-11-13T22:17:21+00:00"
first_seen_at: "2026-11-13T22:33:34+00:00"
updated_at: "2026-11-13T22:35:18+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-110279", "first_seen_at": "2026-11-13T22:33:34+00:00"}, {"source": "analyst", "url": "https://www.ibm.com/support/pages/node/7296490", "first_seen_at": "2026-11-13T22:35:18+00:00", "cites": ["https://www.ibm.com/support/pages/node/7296490", "https://github.com/IBM/mcp-context-forge/pull/7341"]}]
exploit_sources: []
---

# IBM ContextForge MCP Gateway: header overrides upstream credentials, bypassing per-user permissions

Link for people: https://infrastack.ai/live/CVE-2026-110279 (this .md is for agents)

IBM ContextForge MCP Gateway versions 1.0.0 through 1.1.0 let the X-Upstream-Authorization request header replace the gateway-managed credential used for upstream calls. An authenticated user can make upstream requests under a different credential, bypassing per-user permissions and audit attribution.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:IBM ContextForge MCP Gateway affected >= 1.0.0, <= 1.1.0 fixed 1.1.1

## How to check

- Check installed ContextForge MCP Gateway version: affected is v1.0.0 through v1.1.0; fixed in v1.1.1
- Check whether any gateway uses auth_type oauth (authorization_code or client_credentials), bearer, basic or authheaders; those are the affected modes
- Check whether clients can send X-Upstream-Authorization through your proxy to MCP endpoints

## Fix

Upgrade IBM ContextForge MCP Gateway to v1.1.1 (fix PR IBM/mcp-context-forge#7341). Workaround if you cannot upgrade: remove the X-Upstream-Authorization request header at the reverse proxy or API gateway in front of ContextForge for all MCP endpoints, and restrict network access to MCP endpoints to trusted networks.

## Timeline

- 2026-11-13T22:33:34+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-110279
- 2026-11-13T22:35:18+00:00 analyst https://www.ibm.com/support/pages/node/7296490 — IBM bulletin 7296490: affected v1.0.0-v1.1.0, fix v1.1.1, workaround: strip X-Upstream-Authorization at proxy and restrict network access to MCP endpoints. No exploitation/PoC seen. Bulletin fix table lists '2.0' in version column; fix text says v1.1.1.

## Documents

- [advisory] IBM Security Bulletin: ContextForge MCP Gateway improper authentication (CVE-2026-110279) https://www.ibm.com/support/pages/node/7296490
- [fix] Fixing PR #7341 mcp-context-forge https://github.com/IBM/mcp-context-forge/pull/7341

## From the sources

IBM ContextForge MCP Gateway 1.0.0 through 1.1.0 is vulnerable to improper credential handling because the X-Upstream-Authorization request header can override the gateway-managed upstream credential for OAuth (authorization_code and client_credentials), bearer and basic authenticated gateways, which could allow an authenticated user to cause upstream requests to be made with a different credential and bypass per-user permission and audit attribution.

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