T05 · Unauthorized Access and Privilege Escalation
Error
- Location
- scripts/bot.py:91
- Finding
- Unrestricted Bot Access Permits Abuse of the Owner's Paid OpenAI API<![CDATA[ ## Vulnerability Details **File Location**: `scripts/bot.py:31-59` and `scripts/bot.py:91-93` **Vulnerability Type**: Missing authorization and resource-consumption controls **Risk Level**: High ### Vulnerable Code ```python async def handle_voice(update: Update, context: ContextTypes.DEFAULT_TYPE) -> None: """Sprachnachricht oder Audio transkribieren.""" msg = update.message audio = msg.voice or msg.audio or msg.video_note if not audio: return log.info("Audio empfangen von %s (%d bytes)", msg.from_user.first_name, audio.file_size or 0) try: # Datei von Telegram herunterladen tg_file = await audio.get_file() suffix = ".ogg" if msg.audio and msg.audio.file_name: suffix = Path(msg.audio.file_name).suffix or ".ogg" with tempfile.NamedTemporaryFile(suffix=suffix, delete=False) as tmp: tmp_path = tmp.name await tg_file.download_to_drive(tmp_path) log.info("Transkribiere %s ...", tmp_path) # Whisper API aufrufen with open(tmp_path, "rb") as f: transcript = client.audio.transcriptions.create( model="whisper-1", file=f, response_format="text", ) # Aufräumen os.unlink(tmp_path) text = transcript.strip() if isinstance(transcript, str) else transcript.text.strip() if text: await msg.reply_text(text) log.info("Transkription gesendet (%d Zeichen)", len(text)) else: await msg.reply_text("(Keine Sprache erkannt)") ``` ```python app.add_handler(CommandHandler("start", handle_start)) app.add_handler(MessageHandler(filters.VOICE | filters.AUDIO | filters.VIDEO_NOTE, handle_voice)) app.add_handler(MessageHandler(filters.TEXT & ~filters.COMMAND, handle_text)) ``` ### Technical Analysis The media handler is registered for every Telegram user who can contact the bot. It does not verify ...[truncated 1850 chars]
- Remediation
- <![CDATA[ ## Remediation Suggestions 1. Require an explicit allowlist of Telegram user IDs or chat IDs before downloading any media or invoking OpenAI. 2. Reject unauthorized requests without revealing operational details. 3. Add per-user and global rate limits, including burst and sustained-request limits. 4. Enforce maximum media size and duration before transcription. 5. Limit concurrent transcription jobs with a queue or semaphore. 6. Configure OpenAI project-level spending limits, usage alerts, and a dedicated restricted API key. 7. Record authorization failures and anomalous usage without logging credentials or sensitive transcript contents. 8. Consider restricting the bot to private chats or a controlled Telegram group. Example authorization gate: ```python ALLOWED_USER_IDS = { int(value) for value in os.environ.get("ALLOWED_USER_IDS", "").split(",") if value.strip() } async def handle_voice(update: Update, context: ContextTypes.DEFAULT_TYPE) -> None: msg = update.effective_message user = update.effective_user if not user or user.id not in ALLOWED_USER_IDS: log.warning("Rejected unauthorized Telegram user ID") return # Continue only after authorization. ``` ]]>