{
    "CVE_data_meta": {
        "ASSIGNER": "security-advisories@github.com",
        "ID": "CVE-2021-41194",
        "STATE": "PUBLIC",
        "TITLE": "Improper Access Control in jupyterhub-firstuseauthenticator"
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "product": {
                        "product_data": [
                            {
                                "product_name": "firstuseauthenticator",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_value": "< 1.0.0"
                                        }
                                    ]
                                }
                            }
                        ]
                    },
                    "vendor_name": "jupyterhub"
                }
            ]
        }
    },
    "data_format": "MITRE",
    "data_type": "CVE",
    "data_version": "4.0",
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "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."
            }
        ]
    },
    "impact": {
        "cvss": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 9.1,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
            "version": "3.1"
        }
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "CWE-284: Improper Access Control"
                    }
                ]
            }
        ]
    },
    "references": {
        "reference_data": [
            {
                "name": "https://github.com/jupyterhub/firstuseauthenticator/security/advisories/GHSA-5xvc-vgmp-jgc3",
                "refsource": "CONFIRM",
                "url": "https://github.com/jupyterhub/firstuseauthenticator/security/advisories/GHSA-5xvc-vgmp-jgc3"
            },
            {
                "name": "https://github.com/jupyterhub/firstuseauthenticator/pull/38",
                "refsource": "MISC",
                "url": "https://github.com/jupyterhub/firstuseauthenticator/pull/38"
            },
            {
                "name": "https://github.com/jupyterhub/firstuseauthenticator/pull/38.patch",
                "refsource": "MISC",
                "url": "https://github.com/jupyterhub/firstuseauthenticator/pull/38.patch"
            }
        ]
    },
    "source": {
        "advisory": "GHSA-5xvc-vgmp-jgc3",
        "discovery": "UNKNOWN"
    }
}