Executive brief
DocsGPT, an AI-powered document analysis platform, fails to validate the origin of requests in its OAuth callback handler. This allows attackers to intercept OAuth session tokens and provider account emails during the authorization flow, and potentially disconnect users' cloud storage integrations.
Technical details
DocsGPT through version 0.20.0 contains a missing origin validation vulnerability in the callback-status OAuth endpoint. The endpoint posts OAuth connector session tokens and provider account emails to a wildcard target origin without verifying the sender's origin, violating same-origin policy protections. An attacker can position themselves as window.opener during an OAuth authorization flow to intercept these sensitive tokens. With intercepted tokens, an attacker can disconnect victims' cloud storage connectors and potentially access or manipulate linked cloud resources. This vulnerability requires user interaction (the user must initiate OAuth flow) but does not require authentication from the attacker.
Affected products
- arc53 DocsGPT through 0.20.0
Timeline
- 2026-09-14: disclosed