CVE-2021-41194

FirstUseAuthenticator is a JupyterHub authenticator that helps new users set their password on their first login to JupyterHub. When JupyterHub is used with FirstUseAuthenticator, a vulnerability in versions prior to 1.0.0 allows unauthorized access to any user's account if `create_users=True` and the username is known or guessed. One may upgrade to version 1.0.0 or apply a patch manually to mitigate the vulnerability. For those who cannot upgrade, there is no complete workaround, but a partial mitigation exists. One can disable user creation with `c.FirstUseAuthenticator.create_users = False`, which will only allow login with fully normalized usernames for already existing users prior to jupyterhub-firstuserauthenticator 1.0.0. If any users have never logged in with their normalized username (i.e. lowercase), they will still be vulnerable until a patch or upgrade occurs.

CVSS v3.0 9.8 CRITICAL
CVSS v2.0 6.8 MEDIUM

9.8^/10

CVSS v3.0 : CRITICAL

V3 Legend

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

6.8^/10

CVSS v2.0 : MEDIUM

V2 Legend

Vector : AV:N/AC:M/Au:N/C:P/I:P/A:P

Exploitability : 8.6 / Impact : 6.4

Access Vector NETWORK

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://github.com/jupyterhub/firstuseauthenticator/pull/38.patch	Patch Third Party Advisory
https://github.com/jupyterhub/firstuseauthenticator/security/advisories/GHSA-5xvc-vgmp-jgc3	Third Party Advisory
https://github.com/jupyterhub/firstuseauthenticator/pull/38	Patch Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:jupyterhub:first_use_authenticator:*:*:*:*:*:*:*:*

Information

Published : 2021-10-28 13:15

Updated : 2021-11-03 05:26

NVD link : CVE-2021-41194

Mitre link : CVE-2021-41194

JSON object : View

CWE

NVD-CWE-noinfo

Products Affected

jupyterhub

first_use_authenticator

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9.8 /10