Description

TypeBot is a chatbot builder tool. Versions prior to 3.17.0 allow a low-privilege guest member of a workspace to obtain a live Google Sheets OAuth access token for that workspace by calling the Google Sheets helper `getAccessToken`. The vulnerable path checks only whether the caller has read access to the workspace, decrypts the stored Google OAuth credential, refreshes or retrieves the access token through the Google client, and returns the raw bearer token directly to the caller. Because guest members can also enumerate credential identifiers, a guest can mint and reuse the workspace's Google access token outside Typebot. Version 3.17.0 patches the issue.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.6",
  "pubDate": "2026-08-11T18:17:33.470Z",
  "pubdate": "2026-08-11T18:17:33.470Z",
  "executiveSummary": "A privilege boundary enforcement vulnerability exists in Typebot prior to version 3.17.0, specifically within the Google Sheets integration helper function. The vulnerability allows unauthorized low-privilege guest members within a workspace to improperly retrieve raw, live Google Sheets OAuth access tokens. The root cause stems from inadequate access control validation that incorrectly checks only for general workspace read access rather than administrative or integration management privileges before decrypting and returning sensitive cryptographic material. Attackers possessing low-privilege guest access can enumerate credential identifiers and invoke the vulnerable Google Sheets helper getAccessToken function directly. This exposes active bearer tokens to unauthorized entities, enabling the minting, hijacking, and external reuse of the workspace's Google OAuth credentials outside the intended boundaries of the Typebot application. The risk implications include unauthorized access to connected Google Sheets resources, potential data exfiltration, and compromise of downstream integrated services. Exploitation requires authenticated guest access to a target workspace but bypasses higher privilege checks, granting unauthorized administrative capabilities regarding external OAuth integrations.",
  "technicalDetails": "The vulnerability resides in Typebot versions prior to 3.17.0 within the Google Sheets helper component, specifically handling the getAccessToken function. The root cause is an improper authorization check implemented during the processing of Google Sheets integration requests. Instead of verifying that the requesting security principal holds administrative or specific integration management privileges over the targeted workspace, the access control check validates only whether the caller possesses basic read access. Because low-privilege guest members satisfy this overly permissive read access criteria, they are improperly granted access to sensitive backend execution paths.\nThe step-by-step attack flow begins with an authenticated attacker possessing low-privilege guest membership within a target Typebot workspace. The attacker proceeds to enumerate workspace credential identifiers, a capability unnecessarily exposed to guest-level roles. Armed with valid credential identifiers, the attacker invokes the Google Sheets helper function getAccessToken. Upon receiving this request, the vulnerable backend logic accepts the input from the low-privilege user, bypasses granular privilege enforcement, and accesses the stored encrypted Google OAuth credential associated with the workspace. The application then decrypts the stored credential material, interacts with the Google client library to refresh or retrieve a live OAuth access token, and returns the raw bearer token directly in the response payload to the caller.\nPost-exploitation impact includes the total compromise of the workspace's Google OAuth session. Because the raw bearer token is returned directly to the low-privilege guest, the attacker can extract the token and reuse it externally outside the Typebot application architecture. This grants the attacker direct programmatic access to the organization's connected Google Sheets and any associated resources accessible via the granted OAuth scopes, entirely circumventing application-layer monitoring and logging controls present in Typebot."
}