cvelist/2021/32xxx/CVE-2021-32727.json

{
    "CVE_data_meta": {
        "ASSIGNER": "security-advisories@github.com",
        "ID": "CVE-2021-32727",
        "STATE": "PUBLIC",
        "TITLE": "End-to-end encryption device setup did not verify public key"
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "product": {
                        "product_data": [
                            {
                                "product_name": "security-advisories",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_value": "< 3.16.1"
                                        }
                                    ]
                                }
                            }
                        ]
                    },
                    "vendor_name": "nextcloud"
                }
            ]
        }
    },
    "data_format": "MITRE",
    "data_type": "CVE",
    "data_version": "4.0",
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "Nextcloud Android Client is the Android client for Nextcloud. Clients using the Nextcloud end-to-end encryption feature download the public and private key via an API endpoint. In versions prior to 3.16.1, the Nextcloud Android client skipped a step that involved the client checking if a private key belonged to a previously downloaded public certificate. If the Nextcloud instance served a malicious public key, the data would be encrypted for this key and thus could be accessible to a malicious actor. The vulnerability is patched in version 3.16.1. As a workaround, do not add additional end-to-end encrypted devices to a user account."
            }
        ]
    },
    "impact": {
        "cvss": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.7,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N",
            "version": "3.1"
        }
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "CWE-295: Improper Certificate Validation"
                    }
                ]
            }
        ]
    },
    "references": {
        "reference_data": [
            {
                "name": "https://github.com/nextcloud/security-advisories/security/advisories/GHSA-5v33-r9cm-7736",
                "refsource": "CONFIRM",
                "url": "https://github.com/nextcloud/security-advisories/security/advisories/GHSA-5v33-r9cm-7736"
            },
            {
                "name": "https://github.com/nextcloud/android/pull/8438",
                "refsource": "MISC",
                "url": "https://github.com/nextcloud/android/pull/8438"
            },
            {
                "name": "https://hackerone.com/reports/1189162",
                "refsource": "MISC",
                "url": "https://hackerone.com/reports/1189162"
            },
            {
                "name": "https://github.com/nextcloud/end_to_end_encryption_rfc/blob/7f002996397faefb664019a97ebb0a1e210f64f0/RFC.md#further-devices",
                "refsource": "MISC",
                "url": "https://github.com/nextcloud/end_to_end_encryption_rfc/blob/7f002996397faefb664019a97ebb0a1e210f64f0/RFC.md#further-devices"
            }
        ]
    },
    "source": {
        "advisory": "GHSA-5v33-r9cm-7736",
        "discovery": "UNKNOWN"
    }
}