Executive brief
OpenClaw is a JavaScript library that integrates Telegram functionality into applications. The library's audio transcription preflight feature can be triggered by unauthorized senders before proper authentication checks are enforced, allowing attackers to consume excessive server resources or incur unexpected transcription service costs without permission.
Technical details
The vulnerability is a resource consumption issue (CWE-408, CWE-770) in OpenClaw's Telegram audio preflight transcription mechanism. Unauthorized Telegram group senders can trigger expensive audio transcription operations before the allowlist authorization check is enforced. The attack is network-accessible, requires no authentication from the attacker's perspective (any Telegram group member can send audio), and can be exploited at scale to exhaust server resources or drive up API billing costs. Patches are available in version 2026.3.31 and later.
Affected products
- OpenClaw OpenClaw <=2026.3.28
Timeline
- 2026-04-03: disclosed: Advisory published (GHSA-m6fx-m8hc-572m)