CVE-2026-108752
JupyterHub through 6.0.1 OAuth Client ID Collision via Unescaped Hyphen
jupyterhub jupyterhub
CVSS
2.3LowExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.24%Chance of exploitation activity in the next 30 days, higher than 14% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed inNone listedNo source names a fixed version. Check the vendor advisory below
What fixes it
No source in this snapshot names a fixed version. The vendor advisories under References are the place to check.
Description
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.
Text from CVE List
Affected versions 1
- jupyterhubaffected: all versions through 6.0.1CVE List
References 6
- hackmd.io/@haind/jupyterhub-oauth-client-id-cross-user-collisionAdvisoryvia CVE List
- vulncheck.com/advisories/jupyterhub-through-6.0.1-oauth-client-id-collision-via-unescaped-hyphenAdvisoryvia CVE List
- github.com/jupyterhub/jupyterhub/blob/3e516c6f382b481e815ec455befb2f14d80d337b/jupyterhub/user.py#L563-L567Referencevia CVE List
- github.com/jupyterhub/jupyterhub/blob/3e516c6f382b481e815ec455befb2f14d80d337b/jupyterhub/oauth/provider.py#L719-L754Referencevia CVE List
- github.com/jupyterhub/jupyterhub/blob/3e516c6f382b481e815ec455befb2f14d80d337b/jupyterhub/user.py#L1174-L1186Referencevia CVE List
- github.com/jupyterhub/jupyterhubReferencevia CVE List