Yao v1.0.0-rc22 Authorization Bypass Exposes Team Data

Executive Summary

This vulnerability in Yao through v1.0.0-rc22 allows authenticated users to access team records without proper authorization. Specifically, the GET /user/teams/:id endpoint fails to verify if the user belongs to or owns the team, enabling any logged-in user to retrieve sensitive team data like names, descriptions, owner details, and settings by providing a known team ID.

Useful 0 Not Useful 0

Detection Guidance

To detect this vulnerability, check if your Yao application version is v1.0.0-rc22 or earlier. Use API testing tools like curl to send authenticated requests to GET /user/teams/:id with various team IDs. If team data is returned without proper authorization checks, the vulnerability exists.

Example command: curl -H 'Authorization: Bearer <token>' http://<yao-server>/user/teams/1. If sensitive team details are accessible without ownership verification, the system is vulnerable.

Useful 0 Not Useful 0

Impact Analysis

An attacker with a valid account could exploit this to read private team information, even after being removed from the team. This could lead to unauthorized data exposure, potential data leaks, or misuse of team settings. The impact includes privacy violations and possible privilege escalation if team data is used to gain further access.

Useful 0 Not Useful 0

Compliance Impact

This vulnerability likely violates data protection principles under GDPR and HIPAA by exposing sensitive team data without proper access controls. GDPR requires strict data access and authorization, while HIPAA mandates safeguards for protected health information. Unauthorized access risks non-compliance, potential fines, and reputational damage.

Useful 0 Not Useful 0

Mitigation Strategies

Upgrade Yao to the latest version beyond v1.0.0-rc22 immediately. If upgrading is not possible, restrict access to the /user/teams/:id endpoint by implementing proper authorization checks to verify team ownership or membership before returning data.

Review all team-related API endpoints to ensure consistent permission validation. Remove or disable any commented-out access control checks that may bypass security measures.

Useful 0 Not Useful 0