CVE-2026-54338

MEDIUM

CVE: CVE-2026-54338 - JupyterHub is software that allows users to create a multi-user server for Jupyter notebooksSign in to save

CVSS

5.3

CVSS v3.1

EPSS

0.3%

Exploit Prediction Score

Published

August 7, 2026

Exploitability

EPSS probability 0.3%

Description

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.

Weaknesses

CWE-400

Affected Packages

No package data available.

Aliases

CVE-2026-54338

Related references

Publisher and database URLs for this record (shown for attribution; reading stays in Bugflare).

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