OpenClaw Telegram webhook request bodies were read before secret validation, enabling unauthenticated resource exhaustion

Summary

openclaw versions <= 2026.3.12 read and buffered Telegram webhook request bodies before validating x-telegram-bot-api-secret-token. This let unauthenticated callers force up to the configured webhook body limit of pre-auth body I/O and JSON parse work per request.

Affected Packages / Versions

• Package: openclaw (npm)
• Affected versions: <= 2026.3.12
• Fixed version: 2026.3.13

Details

The vulnerable path was the standalone Telegram webhook listener in src/telegram/webhook.ts. In affected releases, the request handler accepted POST requests, called readJsonBodyWithLimit(...), and only then checked the Telegram secret header. Because the secret validation happened after body reading, an unauthenticated caller could make the server spend memory, socket time, and JSON parse work on requests that should have been rejected before any body processing.

This issue is in scope under OpenClaw's trust model because the Telegram webhook endpoint accepts untrusted network traffic and the secret header is the authentication boundary for that ingress path.

Fix

openclaw@2026.3.13 validates the Telegram webhook secret before any body I/O. Current code reads the header, rejects invalid requests immediately with 401, and only calls readJsonBodyWithLimit(...) after hasValidTelegramWebhookSecret(...) succeeds.

Regression coverage exists in src/telegram/webhook.test.ts (rejects unauthenticated requests before reading the request body).

Fix Commit(s)

• 7e49e98f79073b11134beac27fdff547ba5a4a02

Thanks @space08 for reporting.