diff --git a/lib/public/Util.php b/lib/public/Util.php
index be42d1600be89..7bf6db9a6e86e 100644
--- a/lib/public/Util.php
+++ b/lib/public/Util.php
@@ -522,7 +522,27 @@ public static function needUpgrade() {
 	 * @return bool true if the url is valid, false otherwise.
 	 * @since 23.0.0
 	 */
-	public static function isValidUrl(string $url): bool {
-		return filter_var(idn_to_ascii($url), FILTER_VALIDATE_URL) !== false;
+	public static function isValidUrl(string $url, array $protocols = ['http', 'https']): bool {
+		// from https://github.com/symfony/validator/blob/14337bdf9e2e0b2e3385c9e90f13325f0c95a4f9/Constraints/UrlValidator.php#L24
+		// Author: Bernhard Schussek <bschussek@gmail.com>
+		$pattern = '~^
+			(%s)://                                 # protocol
+			(((?:[\_\.\pL\pN-]|%%[0-9A-Fa-f]{2})+:)?((?:[\_\.\pL\pN-]|%%[0-9A-Fa-f]{2})+)@)?  # basic auth
+			(
+				([\pL\pN\pS\-\_\.])+(\.?([\pL\pN]|xn\-\-[\pL\pN-]+)+\.?)        # a domain name
+					|                                                           # or
+				\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}                              # an IP address
+					|                                                           # or
+				\[
+					(?:(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){6})(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:::(?:(?:(?:[0-9a-f]{1,4})):){5})(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:[0-9a-f]{1,4})))?::(?:(?:(?:[0-9a-f]{1,4})):){4})(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,1}(?:(?:[0-9a-f]{1,4})))?::(?:(?:(?:[0-9a-f]{1,4})):){3})(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,2}(?:(?:[0-9a-f]{1,4})))?::(?:(?:(?:[0-9a-f]{1,4})):){2})(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,3}(?:(?:[0-9a-f]{1,4})))?::(?:(?:[0-9a-f]{1,4})):)(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,4}(?:(?:[0-9a-f]{1,4})))?::)(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,5}(?:(?:[0-9a-f]{1,4})))?::)(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,6}(?:(?:[0-9a-f]{1,4})))?::))))
+				\]  # an IPv6 address
+			)
+			(:[0-9]+)?                                                          # a port (optional)
+			(?:/ (?:[\pL\pN\-._\~!$&\'()*+,;=:@]|%%[0-9A-Fa-f]{2})* )*          # a path
+			(?:\? (?:[\pL\pN\-._\~!$&\'\[\]()*+,;=:@/?]|%%[0-9A-Fa-f]{2})* )?   # a query (optional)
+			(?:\# (?:[\pL\pN\-._\~!$&\'()*+,;=:@/?]|%%[0-9A-Fa-f]{2})* )?       # a fragment (optional)
+		$~ixu';
+		$pattern = sprintf($pattern, implode('|', $protocols));
+		return preg_match($pattern, $url);
 	}
 }