cvelist/2023/2xxx/CVE-2023-2640.json

{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2023-2640",
        "ASSIGNER": "security@ubuntu.com",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "On Ubuntu kernels carrying both c914c0e27eb0 and \"UBUNTU: SAUCE: overlayfs: Skip permission checking for trusted.overlayfs.* xattrs\", an unprivileged user may set privileged extended attributes on the mounted files, leading them to be set on the upper files without the appropriate security checks."
            }
        ]
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "CWE-863",
                        "cweId": "CWE-863"
                    }
                ]
            }
        ]
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "vendor_name": "Canonical",
                    "product": {
                        "product_data": [
                            {
                                "product_name": "Ubuntu Kernel",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "status": "unaffected",
                                                        "version": "0",
                                                        "lessThan": "6.2.0-26.26",
                                                        "versionType": "semver"
                                                    },
                                                    {
                                                        "status": "unaffected",
                                                        "version": "0",
                                                        "lessThan": "6.0.0-1020.20",
                                                        "versionType": "semver"
                                                    },
                                                    {
                                                        "status": "unaffected",
                                                        "version": "0",
                                                        "lessThan": "5.4.0-155.172",
                                                        "versionType": "semver"
                                                    }
                                                ],
                                                "defaultStatus": "unaffected"
                                            }
                                        }
                                    ]
                                }
                            }
                        ]
                    }
                }
            ]
        }
    },
    "references": {
        "reference_data": [
            {
                "url": "https://ubuntu.com/security/notices/USN-6250-1",
                "refsource": "MISC",
                "name": "https://ubuntu.com/security/notices/USN-6250-1"
            },
            {
                "url": "https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-2640",
                "refsource": "MISC",
                "name": "https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-2640"
            },
            {
                "url": "https://wiz.io/blog/ubuntu-overlayfs-vulnerability",
                "refsource": "MISC",
                "name": "https://wiz.io/blog/ubuntu-overlayfs-vulnerability"
            },
            {
                "url": "https://lists.ubuntu.com/archives/kernel-team/2023-July/140923.html",
                "refsource": "MISC",
                "name": "https://lists.ubuntu.com/archives/kernel-team/2023-July/140923.html"
            }
        ]
    },
    "work_around": [
        {
            "lang": "en",
            "value": "If not needed, disable the ability for unprivileged users\nto create namespaces. To do this temporarily, do:\n  sudo sysctl -w kernel.unprivileged_userns_clone=0\nTo disable across reboots, do:\n  echo kernel.unprivileged_userns_clone=0 | \\\n  sudo tee /etc/sysctl.d/99-disable-unpriv-userns.conf"
        }
    ],
    "credits": [
        {
            "lang": "en",
            "value": "Stonejiajia"
        },
        {
            "lang": "en",
            "value": "Shir Tamari"
        },
        {
            "lang": "en",
            "value": "Sagi Tzadik"
        }
    ],
    "impact": {
        "cvss": [
            {
                "version": "3.1",
                "attackVector": "LOCAL",
                "attackComplexity": "LOW",
                "privilegesRequired": "LOW",
                "userInteraction": "NONE",
                "scope": "UNCHANGED",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "availabilityImpact": "HIGH",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                "baseScore": 7.8,
                "baseSeverity": "HIGH"
            }
        ]
    }
}