Juniper versions prior to 0.17.2 contain a stack overflow vulnerability triggered by deeply nested GraphQL documents. The parser recursively processes each nesting level without limits, allowing an attacker to cause a stack overflow by submitting documents with excessive nesting or long chains of fragment spreads. This results in the server process aborting and dropping all ongoing requests. The vulnerability requires no authentication to exploit. Version 0.17.2 and later mitigate this by enforcing limits on nesting depth and token count.