Vulnerability in Jupyterhub
CVE-2026-108752
JupyterHub through 6.0.1 contains an identifier collision vulnerability that allows authenticated users to overwrite another user's named-server OAuth client by registering a hyphenated username. Attackers holding a name like alice-prod can overwrite the client for alice's server prod, breaking OAuth login and revoking tokens by stopping their own server.
Published .
CVSS v3 metric
CVSS v3 base score 4.2 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:L.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- hackmd.io/@haind/jupyterhub-oauth-client-id-cross-user-collision (third-party-advisory)
- github.com/jupyterhub/jupyterhub/blob/3e516c6f382b481e815ec455befb2f14d80d337b/… (technical-description)
- github.com/jupyterhub/jupyterhub/blob/3e516c6f382b481e815ec455befb2f14d80d337b/… (technical-description)
- github.com/jupyterhub/jupyterhub/blob/3e516c6f382b481e815ec455befb2f14d80d337b/… (technical-description)
- github.com/jupyterhub/jupyterhub (product)
- www.vulncheck.com/advisories/jupyterhub-through-6.0.1-oauth-client-id-collision… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-108752?
- CVE-2026-108752 is a medium-severity vulnerability in Jupyterhub, classified under Use of Multiple Resources with Duplicate Identifier. CVSS score: 4.2/10. Published 2026-10-11.
- How severe is CVE-2026-108752?
- Medium severity. CVSS v3 base score is 4.2 out of 10.