diff --git a/cache/stores/redis/lib.php b/cache/stores/redis/lib.php
index bcf56fddbbf..83a58892e5b 100644
--- a/cache/stores/redis/lib.php
+++ b/cache/stores/redis/lib.php
@@ -325,7 +325,7 @@ class cachestore_redis extends cache_store implements cache_is_key_aware, cache_
      * @return bool True if the key exists, false if it does not.
      */
     public function has($key) {
-        return $this->redis->hExists($this->hash, $key);
+        return !empty($this->redis->hExists($this->hash, $key));
     }
 
     /**
diff --git a/lib/classes/session/redis.php b/lib/classes/session/redis.php
index fefab50d7d6..a669996e764 100644
--- a/lib/classes/session/redis.php
+++ b/lib/classes/session/redis.php
@@ -396,7 +396,7 @@ class redis extends handler {
         }
 
         try {
-            return $this->connection->exists($sid);
+            return !empty($this->connection->exists($sid));
         } catch (RedisException $e) {
             return false;
         }