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.

CVSS v3 4.2 MEDIUM

4.2^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/jupyterhub/jupyterhub
https://github.com/jupyterhub/jupyterhub/blob/3e516c6f382b481e815ec455befb2f14d80d337b/jupyterhub/oauth/provider.py#L719-L754
https://github.com/jupyterhub/jupyterhub/blob/3e516c6f382b481e815ec455befb2f14d80d337b/jupyterhub/user.py#L1174-L1186
https://github.com/jupyterhub/jupyterhub/blob/3e516c6f382b481e815ec455befb2f14d80d337b/jupyterhub/user.py#L563-L567
https://hackmd.io/@haind/jupyterhub-oauth-client-id-cross-user-collision
https://www.vulncheck.com/advisories/jupyterhub-through-6.0.1-oauth-client-id-collision-via-unescaped-hyphen

Configurations

No configuration.

History

11 Oct 2026, 13:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-11 13:17

Updated : 2026-10-16 17:25

NVD link : CVE-2026-108752

Mitre link : CVE-2026-108752

CVE.ORG link : CVE-2026-108752

JSON object : View

Products Affected

No product.

CWE

CWE-694

Use of Multiple Resources with Duplicate Identifier

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