A vulnerability in danswer-ai/danswer version 0.9.0 allows for denial of service through memory exhaustion. The issue arises from the use of a vulnerable version of the starlette package (<=0.49) via fastapi, which was patched in fastapi version 0.115.3. The vulnerability can be exploited by sending multiple requests to the /auth/saml/callback endpoint, leading to uncontrolled memory consumption and eventual denial of service.