ContextForge: DNS TOCTOU race condition causes SSRF protection bypass (`/admin/gateways/test`) (CVE-2026-53708) | HOL Guard CVE

Medium severityCVE-2026-53708GHSA-9HGC-G3W5-67CM

ContextForge: DNS TOCTOU race condition causes SSRF protection bypass (`/admin/gateways/test`)

Answer in brief

CVE-2026-53708 records a Medium severity vulnerability in ContextForge: DNS TOCTOU race condition causes SSRF protection bypass (`/admin/gateways/test`). The current sources do not mark it as known exploited. The current feed maps IBM/mcp-context-forge (generic), IBM/mcp-contextforge-gateway (generic), mcp-contextforge-gateway (pip). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 14, 2026Updated Sep 14, 2026Source checked Sep 14, 2026First seen by HOL Aug 14, 2026Material review Sep 14, 2026

Upstream Advisory

Key facts

Risk: Medium
Exploitation: Not marked as known exploited
Affected software: 3 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps IBM/mcp-context-forge (generic), IBM/mcp-contextforge-gateway (generic), mcp-contextforge-gateway (pip). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
IBM/mcp-context-forgegeneric	< 1.0.3	Not reported
IBM/mcp-contextforge-gatewaygeneric	< 1.0.3	Not reported
mcp-contextforge-gatewaypip	<1.0.3	1.0.3

Recommended response

Check inventory. Check lockfiles and deployed manifests for IBM/mcp-context-forge, IBM/mcp-contextforge-gateway, mcp-contextforge-gateway.
Review the reported fix. Update mcp-contextforge-gateway to 1.0.3 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 14, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 14, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 14, 2026

Sources and claim methodology

Upstream source description

ContextForge is an AI gateway, registry, and proxy that provides centralized discovery, guardrails, and management for MCP, A2A, and REST or gRPC APIs. Prior to 1.0.3, the /admin/gateways/test call site in mcpgateway/admin.py calls validate_gateway_test_url() in mcpgateway/common/validators.py to resolve and reject private, loopback, link-local, and cloud-metadata addresses, but ResilientHttpClient later resolves the original hostname again without binding the validated address. When MCPGATEWAY_ADMIN_API_ENABLED is enabled, an attacker with a database-backed role containing explicit gateways.read permission can use DNS rebinding to return a public address during validation and a private or metadata address during connection, bypassing ssrf_blocked_networks and ssrf_dns_fail_closed because those controls apply only to the validation-time result. The endpoint's allow_admin_bypass=False setting means a bootstrap-only virtual platform-admin identity without a database role is not sufficient. Successful exploitation can reach internal services and cloud metadata, expose cloud credentials, access internal APIs, or probe internal network ports. This issue is fixed in version 1.0.3.

Quoted source text, attributed separately from HOL analysis.