<?php 
    
    $objectManager = \Magento\Framework\App\ObjectManager::getInstance();
    $item = $objectManager->create('Magento\Catalog\Model\Product');
    $quoteId = $objectManager-> create('Magento\Checkout\Model\Session')->getQuoteId();
    $cartData = $objectManager->create('Magento\Quote\Model\QuoteRepository')->get($quoteId)->getAllVisibleItems(); 
    
    foreach($items as $item) {
    	$item = $item->load($item->getProductId());
    
    	if($item->getData('custom_attribute')=='SM100'){
         	echo 'ID: '.$item->getProductId().'<br />';
          	echo 'Name: '.$item->getName().'<br />';
           	echo 'Sku: '.$item->getSku().'<br />';
           	echo 'Quantity: '.$item->getQty().'<br />';
          	echo 'Price: '.$item->getPrice().'<br />';
        	echo "<br />";   
    	}
    
    
      }