CVE-2026-33175

high

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.

References

https://github.com/jupyterhub/oauthenticator/security/advisories/GHSA-rrvg-cxh4-qhrv

https://github.com/jupyterhub/oauthenticator/releases/tag/17.4.0

https://github.com/jupyterhub/oauthenticator/commit/f0c7002dc36e41efae0f674033cf7888a21d96f9

Details

Source: Mitre, NVD

Published: 2026-04-03

Updated: 2026-04-03

Risk Information

CVSS v2

Base Score: 9

Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:C

Severity: High

CVSS v3

Base Score: 8.8

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Severity: High

EPSS

EPSS: 0.00098