diff --git a/lib/std/string.lua b/lib/std/string.lua
index 6ad9014..2c6f956 100644
--- a/lib/std/string.lua
+++ b/lib/std/string.lua
@@ -133,7 +133,7 @@ end
 
 
 local function escape_shell(s)
-   return(gsub(s, '([ %(%)%\\%[%]\'"])', '\\%1'))
+   return(gsub(s, '([ %(%)%\\%[%]\'"&])', '\\%1'))
 end