oauthenticator: Incorrect Authorization
CVE-2024-37300 is a high-severity incorrect authorization vulnerability in oauthenticator from Jupyterhub, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected oauthenticator versions: < 16.3.1. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.4% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of oauthenticator you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Jupyterhub | oauthenticator | < 16.3.1 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N. Scored by CNA (github.com).
Official description
OAuthenticator is software that allows OAuth2 identity providers to be plugged in and used with JupyterHub. JupyterHub < 5.0, when used with `GlobusOAuthenticator`, could be configured to allow all users from a particular institution only. This worked fine prior to JupyterHub 5.0, because `allow_all` did not take precedence over `identity_provider`. Since JupyterHub 5.0, `allow_all` does take precedence over `identity_provider`. On a hub with the same config, now all users will be allowed to login, regardless of `identity_provider`. `identity_provider` will basically be ignored. This is a documented change in JupyterHub 5.0, but is likely to catch many users by surprise. OAuthenticator 16.3.1 fixes the issue with JupyterHub 5.0, and does not affect previous versions. As a workaround, do not upgrade to JupyterHub 5.0 when using `GlobusOAuthenticator` in the prior configuration.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Incorrect Authorization
The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.
How developers prevent this class of flaw
- Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) to enforce the roles at the appropriate boundaries. Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
- Ensure that access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied to more generic resources such as files, connections, processes, memory, and database records. For example, a database may restrict access for medical records to a specific database user, but each record might only be intended to be accessible to the patient and the patient's doctor.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using authorization frameworks such as the JAAS Authorization Framework and the OWASP ESAPI Access Control feature.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other references
Other vulnerabilities in oauthenticator
- 8.8 High severity
- 9.1 Critical severity
Recent Incorrect Authorization vulnerabilities
- 9.8 Critical severity
- 8.8 High severity
- 7.8 High severity
- 9.8 Critical severity
- 9.4 Critical severity
- 8.8 High severity
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