TYPO3 Core

While trying to log in into backend I'm getting:

Fatal error: Call to undefined method TYPO3\CMS\Core\Utility\CommandUtility::getCommand() in C:\xampp\htdocs\community46\typo3\sysext\rsaauth\Classes\Backend\CommandLineBackend.php on line 60

this line right now is:
$this->opensslPath = \TYPO3\CMS\Core\Utility\CommandUtility::getCommand('openssl');

before was:
$this->opensslPath = t3lib_exec::getCommand('openssl');

Class t3lib_exec is now mapped to \TYPO3\CMS\Core\Extension\ExtensionManager::extPath('core') . 'Classes/Utility/CommandUtility.php';

but the content of CommandUtility is completely different then the original t3lib_exec class