CVE-2026-54338

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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

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

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-07 21:17

Updated : 2026-09-09 20:58

NVD link : CVE-2026-54338

Mitre link : CVE-2026-54338

CVE.ORG link : CVE-2026-54338

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

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