cvelist/2023/34xxx/CVE-2023-34252.json

{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2023-34252",
        "ASSIGNER": "security-advisories@github.com",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "Grav is a file-based Web platform. Prior to version 1.7.42, there is a logic flaw in the `GravExtension.filterFilter()` function whereby validation against a denylist of unsafe functions is only performed when the argument passed to filter is a string. However, passing an array as a callable argument allows the validation check to be skipped. Consequently, a low privileged attacker with login access to Grav Admin panel and page creation/update permissions is able to inject malicious templates to obtain remote code execution. The vulnerability can be found in the `GravExtension.filterFilter()` function declared in `/system/src/Grav/Common/Twig/Extension/GravExtension.php`. Version 1.7.42 contains a patch for this issue. End users should also ensure that `twig.undefined_functions` and `twig.undefined_filters` properties in `/path/to/webroot/system/config/system.yaml` configuration file are set to `false` to disallow Twig from treating undefined filters/functions as PHP functions and executing them."
            }
        ]
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "CWE-184: Incomplete List of Disallowed Inputs",
                        "cweId": "CWE-184"
                    }
                ]
            },
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "CWE-1336: Improper Neutralization of Special Elements Used in a Template Engine",
                        "cweId": "CWE-1336"
                    }
                ]
            }
        ]
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "vendor_name": "getgrav",
                    "product": {
                        "product_data": [
                            {
                                "product_name": "grav",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_affected": "=",
                                            "version_value": "< 1.7.42"
                                        }
                                    ]
                                }
                            }
                        ]
                    }
                }
            ]
        }
    },
    "references": {
        "reference_data": [
            {
                "url": "https://github.com/getgrav/grav/security/advisories/GHSA-96xv-rmwj-6p9w",
                "refsource": "MISC",
                "name": "https://github.com/getgrav/grav/security/advisories/GHSA-96xv-rmwj-6p9w"
            },
            {
                "url": "https://github.com/getgrav/grav/commit/244758d4383034fe4cd292d41e477177870b65ec",
                "refsource": "MISC",
                "name": "https://github.com/getgrav/grav/commit/244758d4383034fe4cd292d41e477177870b65ec"
            },
            {
                "url": "https://github.com/getgrav/grav/blob/1.7.40/system/src/Grav/Common/Twig/Extension/GravExtension.php#L1692-L1698",
                "refsource": "MISC",
                "name": "https://github.com/getgrav/grav/blob/1.7.40/system/src/Grav/Common/Twig/Extension/GravExtension.php#L1692-L1698"
            },
            {
                "url": "https://github.com/getgrav/grav/blob/1.7.40/system/src/Grav/Common/Utils.php#L1956-L2074",
                "refsource": "MISC",
                "name": "https://github.com/getgrav/grav/blob/1.7.40/system/src/Grav/Common/Utils.php#L1956-L2074"
            }
        ]
    },
    "source": {
        "advisory": "GHSA-96xv-rmwj-6p9w",
        "discovery": "UNKNOWN"
    },
    "impact": {
        "cvss": [
            {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 8.8,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                "version": "3.1"
            }
        ]
    }
}