CVE-2026-33175 json
OAuthenticator: Authentication Bypass in Auth0OAuthenticator via Unverified Email Claims
published 7mo ago modified last mo. also EUVD-2026-18878 , GHSA-rrvg-cxh4-qhrv , PYSEC-2026-2238
- cvss
- 8.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 39%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- pypi oauthenticator 17.4.0
- jupyter oauthenticator 17.4.0
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 7mo ago
Exploit prediction
0.45% chance of exploitation in the next 30 days, higher than 39% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| GitHub | 3.1 | 8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| OSV | 3.1 | 8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | oauthenticator | <17.4.0 |
17.4.0 |
Affected products
- jupyterhub oauthenticator
Classification
References
-
github.com
/jupyterhub/oauthenticator/commit/f0c7002dc36e41efae0f674033cf7888a21d96f9
web, patch
-
github.com
/jupyterhub/oauthenticator/security/advisories/GHSA-rrvg-cxh4-qhrv
web, mitigation, vendor-advisory, advisory
-
github.com
/jupyterhub/oauthenticator/releases/tag/17.4.0
web, product
-
nvd.nist.gov
/vuln/detail/CVE-2026-33175
advisory
-
github.com
/jupyterhub/oauthenticator
package
-
support.auth0.com
/center/s/article/Enforce-Email-Verification-With-Sending-Email-After-Each-Denied-Access
web
Sources
- CVE List CVE-2026-33175
- GitHub Advisory GHSA-rrvg-cxh4-qhrv
- NVD CVE-2026-33175
- OSV PYSEC-2026-2238
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.