CVE-2026-53708
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.
What this means for your business
- An attacker can use it remotely, over a network, with an administrator login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.2% chance of attack attempts being seen in the next 30 days, ranking above 14% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 6.6 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:L/A:N- Weakness
- CWE-350
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-09-14
- Last modified
- 2026-09-14
- Sources
- NVD
References
- https://github.com/IBM/mcp-context-forge/commit/fba11a99babd80779fa05510b35fb6a153bbacaf
- https://github.com/IBM/mcp-context-forge/releases/tag/v1.0.3
- https://github.com/IBM/mcp-context-forge/security/advisories/GHSA-9hgc-g3w5-67cm
- https://github.com/IBM/mcp-context-forge/security/advisories/GHSA-9hgc-g3w5-67cm