Security: Replace urllib.request with httpx in WebDAV testing

The `_test_webdav_connection` function previously used `urllib.request.urlopen`
to verify connection credentials. This triggers a Bandit B310 warning because
`urllib` supports multiple schemes (like file://, ftp://) and implicitly follows
redirects.

Although scheme checking and a basic `is_private_ip` validation were implemented,
using `urllib.request` remains risky because a public URL could return an
HTTP redirect to a private IP (e.g., 127.0.0.1) which `urllib` would blindly follow,
causing an SSRF (Server-Side Request Forgery) bypass.

This commit replaces `urllib.request` with `httpx.request` using explicitly
`follow_redirects=False`. This eliminates the B310 vulnerability, ensures
requests only hit the specified URL without following potentially malicious
redirects, and standardizes the application on `httpx` for safer HTTP connections.

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>

.jules/sentinel.md

@@ -2,3 +2,7 @@
 **Vulnerability:** The `_test_webdav_connection` function had a custom SSRF check that failed to resolve DNS names, allowing attackers to bypass the check by providing a domain that resolves to an internal IP (e.g., `127.0.0.1`).
 **Learning:** DNS resolution is required for robust SSRF protection when validating URLs provided by users.
 **Prevention:** Use a centralized `is_private_ip` function (now in `app/utils/network.py`) that resolves the hostname to its IPs and checks if any are private.
+## 2026-03-22 - B310: urllib.request.urlopen replaced with httpx
+**Vulnerability:** The `_test_webdav_connection` function used `urllib.request.urlopen`, which natively supports dangerous schemes like `file://` or `ftp://` and follows redirects by default, potentially allowing SSRF bypasses or Local File Inclusion.
+**Learning:** `urllib.request` should be avoided for user-supplied URLs. Even when URL schemes are manually validated, `urllib`'s default redirect following behavior can bypass SSRF protections (e.g. redirecting to `127.0.0.1`).
+**Prevention:** Use a modern, safer HTTP client like `httpx` with `follow_redirects=False` when testing user-provided URLs.

app/api/integrations.py

@@ -608,7 +608,7 @@ def _test_dropbox_connection(config: dict[str, Any] | None, credentials: dict[st
 
 def _test_webdav_connection(config: dict[str, Any] | None, credentials: dict[str, Any] | None) -> dict[str, Any]:
     """Test a WebDAV/Nextcloud connection by issuing an HTTP PROPFIND."""
-    import urllib.request
+    import httpx
 
     cfg = config or {}
     creds = credentials or {}
@@ -635,17 +635,14 @@ def _test_webdav_connection(config: dict[str, Any] | None, credentials: dict[str
             return {"success": False, "message": "URLs pointing to internal or private networks are not allowed"}
 
     try:
-        import base64
+        auth = (username, password) if username and password else None
+        headers = {"Depth": "0"}
 
-        req = urllib.request.Request(url, method="PROPFIND")  # noqa: S310
-        if username and password:
-            token = base64.b64encode(f"{username}:{password}".encode()).decode()
-            req.add_header("Authorization", f"Basic {token}")
-        req.add_header("Depth", "0")
-        with urllib.request.urlopen(req, timeout=10) as resp:  # noqa: S310
-            if resp.status < 400:
-                return {"success": True, "message": "WebDAV connection successful"}
-            return {"success": False, "message": f"WebDAV returned HTTP {resp.status}"}
+        # Use httpx for secure connection testing, avoiding urllib vulnerabilities
+        resp = httpx.request("PROPFIND", url, auth=auth, headers=headers, timeout=10.0, follow_redirects=False)
+        if resp.status_code < 400:
+            return {"success": True, "message": "WebDAV connection successful"}
+        return {"success": False, "message": f"WebDAV returned HTTP {resp.status_code}"}
     except Exception as exc:  # noqa: BLE001
         logger.warning("WebDAV connection error for %s: %s", hostname, exc)
         return {"success": False, "message": "WebDAV connection failed — check URL and credentials"}