diff --git a/src/rules.js b/src/rules.js
index 322825bbcb..02610c7d26 100644
--- a/src/rules.js
+++ b/src/rules.js
@@ -187,7 +187,7 @@ inline._punctuation = '!"#$%&\'()+\\-.,/:;<=>?@\\[\\]`^{|}~';
inline.punctuation = edit(inline.punctuation).replace(/punctuation/g, inline._punctuation).getRegex();
// sequences em should skip over [title](link), `code`,
-inline.blockSkip = /\[[^\]]*?\]\([^\)]*?\)|`[^`]*?`|<[^>]*?>/g;
+inline.blockSkip = /\[[^[\]]*?\]\([^\(\)]*?\)|`[^`]*?`|<[^<>]*?>/g;
// lookbehind is not available on Safari as of version 16
// inline.escapedEmSt = /(?<=(?:^|[^\\)(?:\\[^])*)\\[*_]/g;
inline.escapedEmSt = /(?:^|[^\\])(?:\\\\)*\\[*_]/g;
diff --git a/test/helpers/load.js b/test/helpers/load.js
index 77cd6a8f1f..4aa650944b 100644
--- a/test/helpers/load.js
+++ b/test/helpers/load.js
@@ -111,9 +111,10 @@ export function loadFiles(dir) {
return obj;
}
- for (const spec of specs) {
+ for (let i = 0; i < specs.length; i++) {
+ const spec = specs[i];
if (!spec.section) {
- spec.section = name;
+ spec.section = `${name}[${i}]`;
}
if (!obj[spec.section]) {
obj[spec.section] = {
diff --git a/test/specs/redos/quadratic_em_mask.cjs b/test/specs/redos/quadratic_em_mask.cjs
new file mode 100644
index 0000000000..e71155e1a4
--- /dev/null
+++ b/test/specs/redos/quadratic_em_mask.cjs
@@ -0,0 +1,18 @@
+module.exports = [
+ {
+ markdown: '['.repeat(100000),
+ html: `${'['.repeat(100000)}
`
+ },
+ {
+ markdown: '[.'.repeat(50000),
+ html: `${'[.'.repeat(50000)}
`
+ },
+ {
+ markdown: '<'.repeat(100000),
+ html: `${'<'.repeat(100000)}
`
+ },
+ {
+ markdown: '<.'.repeat(50000),
+ html: `${'<.'.repeat(50000)}
`
+ }
+];