diff --git a/bin/functionMetadata_original.php b/bin/functionMetadata_original.php
index 2f96e528e4..65587bd097 100644
--- a/bin/functionMetadata_original.php
+++ b/bin/functionMetadata_original.php
@@ -63,6 +63,8 @@
 	// continue functionMap.php, line 424
 	'count' => ['hasSideEffects' => false],
 	'sprintf' => ['hasSideEffects' => false],
+	'mt_rand' => ['hasSideEffects' => true],
+	'rand' => ['hasSideEffects' => true],
 
 	// methods
 	'DateTime::createFromFormat' => ['hasSideEffects' => false],
diff --git a/resources/functionMetadata.php b/resources/functionMetadata.php
index 1103050f86..c04272916e 100644
--- a/resources/functionMetadata.php
+++ b/resources/functionMetadata.php
@@ -1271,6 +1271,7 @@
 	'msgfmt_parse' => ['hasSideEffects' => false],
 	'msgfmt_parse_message' => ['hasSideEffects' => false],
 	'mt_getrandmax' => ['hasSideEffects' => false],
+	'mt_rand' => ['hasSideEffects' => true],
 	'net_get_interfaces' => ['hasSideEffects' => false],
 	'ngettext' => ['hasSideEffects' => false],
 	'nl2br' => ['hasSideEffects' => false],
@@ -1356,6 +1357,7 @@
 	'quoted_printable_encode' => ['hasSideEffects' => false],
 	'quotemeta' => ['hasSideEffects' => false],
 	'rad2deg' => ['hasSideEffects' => false],
+	'rand' => ['hasSideEffects' => true],
 	'range' => ['hasSideEffects' => false],
 	'rawurldecode' => ['hasSideEffects' => false],
 	'rawurlencode' => ['hasSideEffects' => false],