diff --git trunk/src/wp-admin/includes/class-wp-plugin-install-list-table.php trunk/src/wp-admin/includes/class-wp-plugin-install-list-table.php
index 03c7e81c47..3ff7991fc5 100644
--- trunk/src/wp-admin/includes/class-wp-plugin-install-list-table.php
+++ trunk/src/wp-admin/includes/class-wp-plugin-install-list-table.php
@@ -504,9 +504,9 @@ class WP_Plugin_Install_List_Table extends WP_List_Table {
 
 			$wp_version = get_bloginfo( 'version' );
 
-			$compatible_php = ( empty( $plugin['requires_php'] ) || version_compare( substr( phpversion(), 0, strlen( $plugin['requires_php'] ) ), $plugin['requires_php'], '>=' ) );
-			$tested_wp      = ( empty( $plugin['tested'] ) || version_compare( substr( $wp_version, 0, strlen( $plugin['tested'] ) ), $plugin['tested'], '<=' ) );
-			$compatible_wp  = ( empty( $plugin['requires'] ) || version_compare( substr( $wp_version, 0, strlen( $plugin['requires'] ) ), $plugin['requires'], '>=' ) );
+			$compatible_php = ( empty( $plugin['requires_php'] ) || version_compare( phpversion(), $plugin['requires_php'], '>=' ) );
+			$tested_wp      = ( empty( $plugin['tested'] ) || version_compare( $wp_version, $plugin['tested'], '<=' ) );
+			$compatible_wp  = ( empty( $plugin['requires'] ) || version_compare( $wp_version, $plugin['requires'], '>=' ) );
 
 			$action_links = array();
 
diff --git trunk/src/wp-admin/includes/plugin-install.php trunk/src/wp-admin/includes/plugin-install.php
index 92fdad384d..f2607cb9ef 100644
--- trunk/src/wp-admin/includes/plugin-install.php
+++ trunk/src/wp-admin/includes/plugin-install.php
@@ -756,9 +756,9 @@ function install_plugin_information() {
 	<?php
 	$wp_version = get_bloginfo( 'version' );
 
-	$compatible_php = ( empty( $api->requires_php ) || version_compare( substr( phpversion(), 0, strlen( $api->requires_php ) ), $api->requires_php, '>=' ) );
-	$tested_wp      = ( empty( $api->tested ) || version_compare( substr( $wp_version, 0, strlen( $api->tested ) ), $api->tested, '<=' ) );
-	$compatible_wp  = ( empty( $api->requires ) || version_compare( substr( $wp_version, 0, strlen( $api->requires ) ), $api->requires, '>=' ) );
+	$compatible_php = ( empty( $api->requires_php ) || version_compare( phpversion(), $api->requires_php, '>=' ) );
+	$tested_wp      = ( empty( $api->tested ) || version_compare( $wp_version, $api->tested, '<=' ) );
+	$compatible_wp  = ( empty( $api->requires ) || version_compare( $wp_version, $api->requires, '>=' ) );
 
 	if ( ! $compatible_php ) {
 		echo '<div class="notice notice-error notice-alt"><p>';