Craft CMS vulnerable to Remote Code Execution via validatePath bypass
Date: 2023-08
Affected: composer/craftcms/cms, composer/craftcms/cms
Attack vector: rce
Category: vulnerability-disclosure
Severity: High
CVE: CVE-2023-40035
CWE: CWE-74
CVSS: 7.2 (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H)

### Summary Bypassing the validatePath function can lead to potential Remote Code Execution (Post-authentication, ALLOW_ADMIN_CHANGES=true) ### Details In bootstrap.php, the SystemPaths path is set as below. ```php // Set the vendor path. By default assume that it's 4 levels up from here $vendorPath = $findConfigPath('--vendorPath', 'CRAFT_VENDOR_PATH') ?? dirname(__DIR__, 3); // Set the "project root" path that contains config/, storage/, etc. By default assume that it's up a level from vendor/. $rootPath = $findConfigPath('--basePath', 'CRAFT_BASE_PATH') ?? dirname($vendorPath); // By default the remaining directories will be in the base directory $dotenvPath = $findConfigPath('--dotenvPath', 'CRAFT_DOTENV_PATH') ?? "$rootPath/.env"; $configPath = $findConfigPath('--configPath', 'CRAFT_CONFIG_PATH') ?? "$rootPath/config"; $contentMigrationsPath = $findConfigPath('--contentMigrationsPath', 'CRAFT_CONTENT_MIGRATIONS_PATH') ?? "$rootPath/migrations"; $storagePath = $findConfigPath('--storagePath', 'CRAFT_STORAGE_PATH') ?? "$rootPath/storage"; $templatesPath = $findConfigPath('--templatesPath', 'CRAFT_TEMPLATES_PATH') ?? "$rootPath/templates"; $translationsPath = $findConfigPath('--translationsPath', 'CRAFT_TRANSLATIONS_PATH') ?? "$rootPath/translations"; $testsPath = $findConfigPath('--testsPath', 'CRAFT_TESTS_PATH') ?? "$rootPath/tests"; ``` Because paths are validated based on the /path1/path2 format, this can be bypassed using a file URI scheme such as file:///path1/pa


Mitigations:

Architectural layers (MAESTRO):