CVE-2026-33175: CWE-287: Improper Authentication in jupyterhub oauthenticator
OAuthenticator is software that allows OAuth2 identity providers to be plugged in and used with JupyterHub. Prior to version 17.4.0, an authentication bypass vulnerability in oauthenticator allows an attacker with an unverified email address on an Auth0 tenant to login to JupyterHub. When email is used as the usrname_claim, this gives users control over their username and the possibility of account takeover. This issue has been patched in version 17.4.0.
AI Analysis
Technical Summary
CVE-2026-33175 is an improper authentication vulnerability (CWE-287) in the oauthenticator component of JupyterHub. Before version 17.4.0, oauthenticator allowed an attacker possessing an unverified email address on an Auth0 tenant to bypass authentication and log in to JupyterHub. When the configuration uses email as the username_claim, this vulnerability enables attackers to control usernames and potentially take over accounts. The vulnerability has a CVSS v3.1 score of 8.8, indicating high severity with network attack vector, low attack complexity, and no user interaction required. The vulnerability was patched in oauthenticator version 17.4.0.
Potential Impact
Successful exploitation allows attackers with unverified Auth0 email addresses to bypass authentication and gain unauthorized access to JupyterHub instances. This can lead to full account takeover, compromising confidentiality, integrity, and availability of user accounts and potentially sensitive data within JupyterHub environments.
Mitigation Recommendations
Upgrade oauthenticator to version 17.4.0 or later, where this authentication bypass vulnerability has been fixed. Since the vendor advisory does not provide additional remediation details, applying this official fix is the recommended action. Patch status is confirmed by the vendor stating the issue is resolved in version 17.4.0.
CVE-2026-33175: CWE-287: Improper Authentication in jupyterhub oauthenticator
Description
OAuthenticator is software that allows OAuth2 identity providers to be plugged in and used with JupyterHub. Prior to version 17.4.0, an authentication bypass vulnerability in oauthenticator allows an attacker with an unverified email address on an Auth0 tenant to login to JupyterHub. When email is used as the usrname_claim, this gives users control over their username and the possibility of account takeover. This issue has been patched in version 17.4.0.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-33175 is an improper authentication vulnerability (CWE-287) in the oauthenticator component of JupyterHub. Before version 17.4.0, oauthenticator allowed an attacker possessing an unverified email address on an Auth0 tenant to bypass authentication and log in to JupyterHub. When the configuration uses email as the username_claim, this vulnerability enables attackers to control usernames and potentially take over accounts. The vulnerability has a CVSS v3.1 score of 8.8, indicating high severity with network attack vector, low attack complexity, and no user interaction required. The vulnerability was patched in oauthenticator version 17.4.0.
Potential Impact
Successful exploitation allows attackers with unverified Auth0 email addresses to bypass authentication and gain unauthorized access to JupyterHub instances. This can lead to full account takeover, compromising confidentiality, integrity, and availability of user accounts and potentially sensitive data within JupyterHub environments.
Mitigation Recommendations
Upgrade oauthenticator to version 17.4.0 or later, where this authentication bypass vulnerability has been fixed. Since the vendor advisory does not provide additional remediation details, applying this official fix is the recommended action. Patch status is confirmed by the vendor stating the issue is resolved in version 17.4.0.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-03-17T22:16:36.719Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69d03c020a160ebd926055e1
Added to database: 4/3/2026, 10:15:30 PM
Last enriched: 4/3/2026, 10:30:26 PM
Last updated: 4/6/2026, 3:39:28 AM
Views: 25
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