jupyterhub oauthenticator up to 17.3.x usrname_claim improper authentication

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.4$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in jupyterhub oauthenticator up to 17.3.x. The affected element is an unknown function. This manipulation of the argument usrname_claim causes improper authentication. This vulnerability appears as CVE-2026-33175. The attack may be initiated remotely. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in jupyterhub oauthenticator up to 17.3.x. It has been declared as critical. Affected by this vulnerability is some unknown functionality. The manipulation of the argument usrname_claim with an unknown input leads to a improper authentication vulnerability. The CWE definition for the vulnerability is CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-33175 since 03/17/2026. The exploitation appears to be easy. The attack can be launched remotely. Technical details are known, but no exploit is available.

Upgrading to version 17.4.0 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch f0c7002dc36e41efae0f674033cf7888a21d96f9 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.4

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.8
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper authentication
CWE: CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: oauthenticator 17.4.0
Patch: f0c7002dc36e41efae0f674033cf7888a21d96f9

Timelineinfo

03/17/2026 CVE reserved
04/04/2026 +17 days Advisory disclosed
04/04/2026 +0 days VulDB entry created
04/04/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-rrvg-cxh4-qhrv
Status: Confirmed

CVE: CVE-2026-33175 (🔒)
GCVE (CVE): GCVE-0-2026-33175
GCVE (VulDB): GCVE-100-355273

Entryinfo

Created: 04/04/2026 08:09
Changes: 04/04/2026 08:09 (68)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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