Gui turns red

I don't know how the bug came up, but I was mining and then I stepped on a block, and suddenly the gui turned red (like the picture). No texture pack, no mod, only Minecraft Vanilla. I forced a crash. you can found it in the txt file attached
EDIT: above my head there is a block, and above that block there is lava , so that occurs when you are below lava (without touching it) I suppose