Summary
JupyterHub has Unauthenticated Denial of Service via Unbounded Username Logging on Failed Login
Advisory details
Impact
Invalid input to login resulted in unbounded logging output. Only form-based Authenticators (the default PAM Authenticator, but not the more widely used OAuthenticator) are affected.
Patches
Upgrade to 5.5.0.
Workarounds
Use an Authenticator that doesn't use a login form, such as OAuthenticator.
References
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