NIXPKGS-2026-2373

GitHub issue published 8 hours ago

JupyterHub: Unauthenticated Denial of Service via Unbounded Username Logging on Failed Login

Permalink CVE-2026-54338

5.3 MEDIUM

CVSS version (CVSS): 3.1
Attack Vector (AV): Network (N)
Attack Complexity (AC): Low (L)
Privileges Required (PR): None (N)
User Interaction (UI): None (N)
Scope (S): Unchanged (U)
Confidentiality (C): None (N)
Integrity (I): None (N)
Availability (A): Low (L)
Modified Attack Vector (MAV): Network (N)
Modified Attack Complexity (MAC): Low (L)
Modified Privileges Required (MPR): None (N)
Modified User Interaction (MUI): None (N)
Modified Confidentiality (MC): None (N)
Modified Scope (MS): Unchanged (U)
Modified Integrity (MI): None (N)
Modified Availability (MA): Low (L)

updated 8 hours ago by @LeSuisse Activity log

Created suggestion 2 days, 18 hours ago
@LeSuisse ignored
6 packages
- python313Packages.jupyterhub-systemdspawner
- python314Packages.jupyterhub-systemdspawner
- python313Packages.jupyterhub-tmpauthenticator
- python314Packages.jupyterhub-tmpauthenticator
- python313Packages.jupyterhub-ldapauthenticator
- python314Packages.jupyterhub-ldapauthenticator
8 hours ago
@LeSuisse accepted 8 hours ago
@LeSuisse published on GitHub 8 hours ago

JupyterHub: Unauthenticated Denial of Service via Unbounded Username Logging on Failed Login

JupyterHub is software that allows users to create a multi-user server for Jupyter notebooks. Prior to 5.5.0, invalid input to form-based login authenticators can place an unbounded attacker-controlled username in failed-login logs, allowing an unauthenticated attacker to consume logging and storage resources. This issue is fixed in version 5.5.0.

References

https://github.com/jupyterhub/jupyterhub/security/advisories/GHSA-p43p-whwx-q52h x_refsource_CONFIRM
https://github.com/jupyterhub/jupyterhub/commit/d6dc595f84b7509969686da31d87d6d69e7fce0a x_refsource_MISC

Affected products

jupyterhub

==< 5.5.0JupyterHub is software that allows users to create a multi-user server for Jupyter notebooks. Prior to 5.5.0, invalid input to form-based login authenticators can place an unbounded attacker-controlled username in failed-login logs, allowing an unauthenticated attacker to consume logging and storage resources. This issue is fixed in version 5.5.0.