diff --git a/input/sdl_input.c b/input/sdl_input.c
index 1c332b8396..a5dd282c85 100644
--- a/input/sdl_input.c
+++ b/input/sdl_input.c
@@ -57,6 +57,7 @@ static bool sdl_key_pressed(int key)
 
    int num_keys = 0xFFFF;
    Uint8 *keymap = SDL_GetKeyState(&num_keys);
+   if (sym < 0 || sym >= num_keys)
       return false;
 
    return keymap[sym];