diff --git a/mod/network.php b/mod/network.php
index a2c20ba40a..59e3b80b5b 100644
--- a/mod/network.php
+++ b/mod/network.php
@@ -54,7 +54,7 @@ function network_init(App $a)
 
 	if ($a->argc > 1) {
 		for ($x = 1; $x < $a->argc; $x ++) {
-			if (DI::dtFormat()->isYearMonth($a->argv[$x])) {
+			if (DI::dtFormat()->isYearMonthDay($a->argv[$x])) {
 				$is_a_date_query = true;
 				break;
 			}
@@ -440,7 +440,7 @@ function networkThreadedView(App $a, $update, $parent)
 
 	if ($a->argc > 1) {
 		for ($x = 1; $x < $a->argc; $x ++) {
-			if (DI::dtFormat()->isYearMonth($a->argv[$x])) {
+			if (DI::dtFormat()->isYearMonthDay($a->argv[$x])) {
 				if ($datequery) {
 					$datequery2 = Strings::escapeHtml($a->argv[$x]);
 				} else {
diff --git a/src/Util/DateTimeFormat.php b/src/Util/DateTimeFormat.php
index e29420e9ea..1725a0e02d 100644
--- a/src/Util/DateTimeFormat.php
+++ b/src/Util/DateTimeFormat.php
@@ -181,4 +181,25 @@ class DateTimeFormat
 
 		return true;
 	}
+
+	/**
+	 * Checks, if the given string is a date with the pattern YYYY-MM-DD
+	 *
+	 * @param string $dateString The given date
+	 *
+	 * @return boolean True, if the date is a valid pattern
+	 */
+	public function isYearMonthDay(string $dateString)
+	{
+		$date = DateTime::createFromFormat('Y-m-d', $dateString);
+		if (!$date) {
+			return false;
+		}
+
+		if (DateTime::getLastErrors()['error_count'] || DateTime::getLastErrors()['warning_count']) {
+			return false;
+		}
+
+		return true;
+	}
 }