CVE-2026-53708ContextForge: DNS TOCTOU race condition causes SSRF protection bypass (`/admin/gateways/test`)
- 6.6MediumCVSS base score
- 0.35%Exploitation in 30 daysEPSS · top 71% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
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.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. A reference of the record is tagged as an exploit. CISA's SSVC rates its exploitation: a proof of concept is public.
Show the exploits1
References tagged exploit1 reference
- https://github.com/IBM/mcp-context-forge/security/advisories/GHSA-9hgc-g3w5-67cm (opens in a new tab)x_refsource_CONFIRMexploit
Timeline
ID reserved
By GitHub_M
- 3 months later
· 3 months later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium6.6 | CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:L/A:N |
| NVDNVD · Deferred | 3.1 | Medium6.6 | CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.35% · top 71% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.6.
Affected products
- affected < 1.0.3
IBM · mcp-contextforge-gateway
- affected < 1.0.3
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- PyPImcp-contextforge-gatewayGHSA-9hgc-g3w5-67cm (opens in a new tab)
References
References3
- https://github.com/IBM/mcp-context-forge/security/advisories/GHSA-9hgc-g3w5-67cm (opens in a new tab)x_refsource_CONFIRMexploit
- https://github.com/IBM/mcp-context-forge/commit/fba11a99babd80779fa05510b35fb6a153bbacaf (opens in a new tab)x_refsource_MISC
- https://github.com/IBM/mcp-context-forge/releases/tag/v1.0.3 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-77591 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-9hgc-g3w5-67cm (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-53708)Record last updated .