Craft is a CMS for creating custom digital experiences on the web and beyond. Bypassing the validatePath function can lead to potential remote code execution. This vulnerability can lead to malicious control of vulnerable systems and data exfiltrations. Although the vulnerability is exploitable only in the authenticated users, configuration with ALLOW_ADMIN_CHANGES=true, there is still a potential security threat (Remote Code Execution). This issue has been patched in version 4.4.15 and version 3.8.15.

Affected: Packagist: craftcms/cms

### 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/p…