ROCA: Return Of the Coppersmith Attack

I only have generation 1,2,3 of yubikeys and none of them seem to be able to alter the firmware. They can alter certain aspects of storage on the key but not the 'software' which generates the one time codes or the tools which deal with gpg keys and such. Those seem to be only accessible if I cut open the key and hardware hack.

The closed source applets I don't have much say on.. I never used the keys for opengpg but just for different types of OTP