A flaw in the webhook resume handler allows an authenticated user with read access to any TypeBot instance to resume a suspended webhook session that belongs to a different bot. By supplying a valid typebotId and blockId from the attacker’s own bot along with a foreign live resultId, the handler authorizes the parent bot but resolves the descendant result solely by the resultId. This bypass means the attacker can inject arbitrary webhook JSON into the victim bot’s paused execution, advancing its workflow without any access to the victim bot. The vulnerability is mapped to CWE‑639 (Authorization Bypass Through User‑Controlled Key).

The vulnerability affects all versions of TypeBot provided by baptisteArno:typebot.io released prior to version 3.17.0. Any user who can read a typebot and resume webhook sessions is at risk, regardless of ownership of the target bot.

The CVSS score is 7.1, indicating a high severity with significant impact on confidentiality, integrity, and availability. The EPSS score is less than 1%, implying a low overall exploitation probability at present. The vulnerability is not listed in CISA’s KEV catalog. Exploitation requires an authenticated attacker with read permissions, but does not need any privileged or admin rights. The attack vector is inferred to involve an authenticated web request to the resume endpoint with crafted parameters, because the description specifies the mixing of authorized and foreign identifiers. The patch in version 3.17.0 removes the unchecked resolution by grounding resultId verification in the parent typebot’s context, thereby preventing unauthorized resumption.