diff --git a/packages/istanbul-reports/lib/html/index.js b/packages/istanbul-reports/lib/html/index.js
index c3939974..e7ccd2f7 100644
--- a/packages/istanbul-reports/lib/html/index.js
+++ b/packages/istanbul-reports/lib/html/index.js
@@ -100,7 +100,7 @@ function footerTemplate(details) {
             </div><!-- /wrapper -->
             <div class='footer quiet pad2 space-top1 center small'>
                 Code coverage generated by
-                <a href="https://istanbul.js.org/" target="_blank">istanbul</a>
+                <a href="https://istanbul.js.org/" target="_blank" rel="noopener">istanbul</a>
                 at ${html.escape(details.datetime)}
             </div>
         </div>