The Red Agent POV Exploiting Broken Object-Level Authorization in an Airline GraphQL API
The Red Agent POV: Exploiting Broken Object-Level Authorization in an Airline GraphQL API
This Red Agent POV focuses on Broken Object-Level Authorization (BOLA), diving deep into a critical authorization bypass vulnerability discovered in an airline’s GraphQL booking API. Operating fully autonomously, the Red Agent mapped the backend architecture, established an anonymous session, and verified mass data extraction within 15 minutes. This exploit exposed high-profile passenger data, yielding complete read and write capabilities over active travel itineraries. BOLA occurs when an application fails to validate whether a user has the required permissions to access a specific object or record. It currently occupies the top spot on the OWASP API Security Top 10 list.
The Red Agent discovered that the airline’s GraphQL booking API utilized sequential integer identifiers without implementing backend authorization checks. While the application enforced front-end authentication by generating distinct session tokens for different user roles, downstream API resolvers failed to validate these roles when processing data requests. By submitting sequential booking numbers to these unprotected resolvers, the Red Agent gained unauthenticated access to the passenger database. This permitted the extraction of travel records spanning two years, including names, dates of birth, billing addresses, masked credit cards, and live flight itineraries. Beyond data exfiltration, the anonymous session also possessed the permissions required to modify or delete active bookings. The discovered mutations offered significant operational impact: contactsChange +bookingSet allowed altering contact emails to completely hijack customer accounts; flightDelete could quietly delete flight segments and cancel active trips; groupDivide enabled arbitrarily separating passengers away from their travel groups; priceOverride permitted manually overriding flight pricing structures to zero out costs; and refundIssue /voidRefund allowed issuing unauthorized financial refunds back to arbitrary accounts.
The Red Agent approached the target with zero prior knowledge, relying on reasoning-driven testing. It began by analyzing client-side JavaScript bundles to extract the structural footprint of the backend architecture, discovering the core API gateway and identifying a multi-step token acquisition flow. Armed with a valid anonymous session token, the Red Agent issued a comprehensive GraphQL introspection query to dynamically map the backend schema. The response revealed a massive footprint: 514 queries and 428 mutations - all available to the anonymous session. The agent analyzed these mutations, flagging several sensitive operations that accepted simple integer parameters like bookingRetrieveByBookingId. It hypothesized these endpoints might lack proper backend validation. The breakthrough occurred when the Red Agent formulated a targeted mutation payload designed to query a specific, predicted integer booking ID.