{"id":"BIT-jupyterhub-2026-108752","summary":"JupyterHub through 6.0.1 OAuth Client ID Collision via Unescaped Hyphen","details":"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.","aliases":["CVE-2026-108752"],"modified":"2026-10-16T09:45:25.604844190Z","published":"2026-10-16T08:38:05.910Z","database_specific":{"severity":"Medium","cpes":["cpe:2.3:a:jupyter:jupyterhub:*:*:*:*:*:python:*:*"]},"references":[{"type":"WEB","url":"https://github.com/jupyterhub/jupyterhub"},{"type":"WEB","url":"https://github.com/jupyterhub/jupyterhub/blob/3e516c6f382b481e815ec455befb2f14d80d337b/jupyterhub/oauth/provider.py#L719-L754"},{"type":"WEB","url":"https://github.com/jupyterhub/jupyterhub/blob/3e516c6f382b481e815ec455befb2f14d80d337b/jupyterhub/user.py#L1174-L1186"},{"type":"WEB","url":"https://github.com/jupyterhub/jupyterhub/blob/3e516c6f382b481e815ec455befb2f14d80d337b/jupyterhub/user.py#L563-L567"},{"type":"WEB","url":"https://hackmd.io/@haind/jupyterhub-oauth-client-id-cross-user-collision"},{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-108752"},{"type":"WEB","url":"https://www.vulncheck.com/advisories/jupyterhub-through-6.0.1-oauth-client-id-collision-via-unescaped-hyphen"}],"affected":[{"package":{"name":"jupyterhub","ecosystem":"Bitnami","purl":"pkg:bitnami/jupyterhub"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"6.1.0"}]}],"database_specific":{"source":"https://github.com/bitnami/vulndb/tree/main/data/jupyterhub/BIT-jupyterhub-2026-108752.json"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:L"}]}],"schema_version":"1.9.0"}