diff --git a/lib/ExpensiMark.js b/lib/ExpensiMark.js
index 3f66cf93..dfc96593 100644
--- a/lib/ExpensiMark.js
+++ b/lib/ExpensiMark.js
@@ -410,7 +410,7 @@ export default class ExpensiMark {
                 regex: /<(b|strong)(?:"[^"]*"|'[^']*'|[^'">])*>([\s\S]*?)<\/\1>(?![^<]*(<\/pre>|<\/code>))/gi,
                 replacement: (match, tagContent, innerContent) => {
                     const fontWeightMatch = innerContent.match(/style="(.*?)"/);
-                    const isFontWeightBold = fontWeightMatch[1].replaceAll(/\s/g,'').includes('font-weight:bold;') || fontWeightMatch[1].replaceAll(/\s/g,'').includes('font-weight:700;')
+                    const isFontWeightBold = fontWeightMatch ? fontWeightMatch[1].replaceAll(/\s/g,'').includes('font-weight:bold;') || fontWeightMatch[1].replaceAll(/\s/g,'').includes('font-weight:700;') : false;
                     const isBold = fontWeightMatch ? isFontWeightBold : true;
                     return isBold ? `*${innerContent}*` : innerContent;
                 },