Possible SSRF via Gatsby _gatsby File Proxy Endpoint
- Category
- webserver
- Author
- HuntRule
- Published
- 2026-09-07
- Updated
- 2026-09-07
ATT&CK techniques
Initial Access → Cred AccessRecon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact
What it detects
This rule detects HTTP requests to the Gatsby /_gatsby/file remote file proxy carrying an absolute URL or a cloud metadata target. Assetnote research showed this static site generator proxy can be coerced into server-side request forgery against internal services and the cloud metadata endpoint.
Reporting behind it
Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.
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