Description
Hubzilla versions prior to 11.4 contains a cross-site request forgery vulnerability in the OAuth2 /authorize endpoint handled by Zotlabs\Module\Authorize::post() that allows unauthenticated attackers to register arbitrary OAuth2 applications under an authenticated user's account by submitting a cross-origin POST request without CSRF token or Origin/Referer validation. Attackers can craft a malicious HTML form that autosubmits attacker-chosen OAuth2 parameters including client_id, client_secret, redirect_uri, and scope to silently register a persistent OAuth2 application, enabling interception of future OAuth2 authorization codes when the victim later authenticates against the attacker-controlled client.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Hubzilla | Hubzilla | < 11.4 | 11.4 |
References
- Product Advisory product
- Proof of Concept Video technical-description
- Patch Commit patch
- https://www.vulncheck.com/advisories/hubzilla-csrf-via-oauth2-authorize-endpoint-app-registration third-party-advisory