diff --git a/lib/private/Avatar/GuestAvatar.php b/lib/private/Avatar/GuestAvatar.php
index c0c7de0c07889..aa515e1ad4b67 100644
--- a/lib/private/Avatar/GuestAvatar.php
+++ b/lib/private/Avatar/GuestAvatar.php
@@ -8,6 +8,7 @@
  */
 namespace OC\Avatar;
 
+use OCP\Color;
 use OCP\Files\SimpleFS\InMemoryFile;
 use OCP\Files\SimpleFS\ISimpleFile;
 use OCP\IConfig;
@@ -88,4 +89,13 @@ public function userChanged(string $feature, $oldValue, $newValue): void {
 	public function isCustomAvatar(): bool {
 		return false;
 	}
+
+
+	/**
+	 * Different color than for authorized user with the same name
+	 * to make it harder to impersonate people.
+	 */
+	public function avatarBackgroundColor(string $hash): Color {
+		return parent::avatarBackgroundColor($hash . ' (guest)');
+	}
 }