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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
Present
Additional conditions required
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
Low
Partial data modification
Availability
Low
Partial disruption
CVSS Vector v4.0
Weakness Type (CWE)
References 6
https://github.com/jupyterhub/jupyterhub
disclosure@vulncheck.com
https://github.com/jupyterhub/jupyterhub/blob/3e516c6f382b481e815ec455befb2f14d…
disclosure@vulncheck.com
https://github.com/jupyterhub/jupyterhub/blob/3e516c6f382b481e815ec455befb2f14d…
disclosure@vulncheck.com
https://github.com/jupyterhub/jupyterhub/blob/3e516c6f382b481e815ec455befb2f14d…
disclosure@vulncheck.com
https://hackmd.io/@haind/jupyterhub-oauth-client-id-cross-user-collision
disclosure@vulncheck.com
https://www.vulncheck.com/advisories/jupyterhub-through-6.0.1-oauth-client-id-c…
disclosure@vulncheck.com