Upgrade Katex to v0.16.10

paige/node_modules/katex/src/utils.js

@@ -93,11 +93,30 @@ export const assert = function<T>(value: ?T): T {
 
 /**
  * Return the protocol of a URL, or "_relative" if the URL does not specify a
- * protocol (and thus is relative).
+ * protocol (and thus is relative), or `null` if URL has invalid protocol
+ * (so should be outright rejected).
  */
-export const protocolFromUrl = function(url: string): string {
-    const protocol = /^\s*([^\\/#]*?)(?::|&#0*58|&#x0*3a)/i.exec(url);
-    return (protocol != null ? protocol[1] : "_relative");
+export const protocolFromUrl = function(url: string): string | null {
+    // Check for possible leading protocol.
+    // https://url.spec.whatwg.org/#url-parsing strips leading whitespace
+    // (U+20) or C0 control (U+00-U+1F) characters.
+    // eslint-disable-next-line no-control-regex
+    const protocol = /^[\x00-\x20]*([^\\/#?]*?)(:|&#0*58|&#x0*3a|&colon)/i
+    .exec(url);
+    if (!protocol) {
+        return "_relative";
+    }
+    // Reject weird colons
+    if (protocol[2] !== ":") {
+        return null;
+    }
+    // Reject invalid characters in scheme according to
+    // https://datatracker.ietf.org/doc/html/rfc3986#section-3.1
+    if (!/^[a-zA-Z][a-zA-Z0-9+\-.]*$/.test(protocol[1])) {
+        return null;
+    }
+    // Lowercase the protocol
+    return protocol[1].toLowerCase();
 };
 
 export default {