diff --git a/[core]/esx_lib/imports/timeout/shared.lua b/[core]/esx_lib/imports/timeout/shared.lua
index c68eec04..e684f3a4 100644
--- a/[core]/esx_lib/imports/timeout/shared.lua
+++ b/[core]/esx_lib/imports/timeout/shared.lua
@@ -7,6 +7,8 @@ local CancelledTimeouts = {}
 ---@param cb function
 ---@return number
 xLib.timeout.setTimeout = function(msec, cb)
+    xLib.verify(cb, "function", true)
+    
     local id <const> = TimeoutCount + 1
 
     SetTimeout(msec, function()