{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-54338", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-06-12T19:23:22.316Z", "datePublished": "2026-08-07T20:52:55.068Z", "dateUpdated": "2026-08-07T20:52:55.068Z"}, "containers": {"cna": {"title": "JupyterHub: Unauthenticated Denial of Service via Unbounded Username Logging on Failed Login", "problemTypes": [{"descriptions": [{"cweId": "CWE-400", "lang": "en", "description": "CWE-400: Uncontrolled Resource Consumption", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L", "version": "3.1"}}], "references": [{"name": "https://github.com/jupyterhub/jupyterhub/security/advisories/GHSA-p43p-whwx-q52h", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/jupyterhub/jupyterhub/security/advisories/GHSA-p43p-whwx-q52h"}, {"name": "https://github.com/jupyterhub/jupyterhub/commit/d6dc595f84b7509969686da31d87d6d69e7fce0a", "tags": ["x_refsource_MISC"], "url": "https://github.com/jupyterhub/jupyterhub/commit/d6dc595f84b7509969686da31d87d6d69e7fce0a"}], "affected": [{"vendor": "jupyterhub", "product": "jupyterhub", "versions": [{"version": "< 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.", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-08-07T20:52:55.068Z"}, "descriptions": [{"lang": "en", "value": "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."}], "source": {"advisory": "GHSA-p43p-whwx-q52h", "discovery": "UNKNOWN"}}}}

{}

{}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,5.5.0)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "jupyterhub", "source": "cna", "vendor": "jupyterhub"}, "product": "jupyterhub", "vendor": "jupyterhub"}], "created": "2026-08-07T22:30:03.063244+00:00", "updated": "2026-08-07T22:30:03.262662+00:00", "vendors": ["jupyterhub", "jupyterhub$PRODUCT$jupyterhub"]}