ETK-2026-1343Zero's internal tracking ID, independent of the CVE number.
waiting for further signalsZero needs more public information before it can validate it.description
FastGPT MCP client connections can be redirected to internal or local addresses because DNS validation is not bound to the address ultimately used for the connection. An authenticated user who can configure an MCP tool URL and controls that hostname's DNS can potentially make FastGPT access internal services in production deployments.
mitigation
Upgrade FastGPT to v4.17.1 or later. Until upgraded, restrict MCP tool creation and updates to trusted administrators and block outbound access to internal, loopback, and cloud metadata networks.
fixed in v4.17.1
outcome
Contextual: an exploit technique exists, but no deterministic check could cover this one.
source signals
Public signals that triggered or updated the pipeline. These are inputs for the deltas above.
- 2026-10-12 09:50Zghsa: trigger signal, started the run
this entry in the feed
GET /api/v1/feed/ETK-2026-1343
{ "etk_id": "ETK-2026-1343", "cve_id": null, "display_id": "ETK-2026-1343", "ghsa_id": "GHSA-x765-6926-7xc9", "euvd_id": null, "status": "published", "anchor_state": "awaiting_cve", "title": "DNS rebinding SSRF in FastGPT MCP client", "summary": "FastGPT MCP client connections can be redirected to internal or local addresses because DNS validation is not bound to the address ultimately used for the connection. An authenticated user who can configure an MCP tool URL and controls that hostname's DNS can potentially make FastGPT access internal services in production deployments.", "mitigation": "Upgrade FastGPT to v4.17.1 or later. Until upgraded, restrict MCP tool creation and updates to trusted administrators and block outbound access to internal, loopback, and cloud metadata networks.", "vendor": null, "product": "FastGPT", "affected": [ { "affected_notes": [], "affected_ranges": [ "<4.17.1" ], "ecosystem": null, "fixed_versions": [ "v4.17.1" ], "package_name": "FastGPT", "purl": null } ], "cwes": [ 367 ], "cvss_score": 9, "cvss_src": "ethiack_provisional", "cvss_vector": null, "epss_score": null, "epss_percentile": null, "epss_asof": null, "automation": "contextual", "check": false, "check_confidence_basis": null, "exploit": false, "pipeline_minutes": 55.31896255, "t0_at": null, "signals": { "trigger_signal": { "at": "2026-10-12T09:50:24+00:00", "days": -8.792402993229167, "is_lower_bound": true, "measured_at": "2026-10-21T04:51:27.640188+00:00", "url": "https://github.com/labring/FastGPT/security/advisories/GHSA-x765-6926-7xc9" } } }
published 2026-10-12 10:27Z
last change 2026-10-21 04:45Z
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