Prevent invalid memory access on crafted signature
Prevent invalid memory access on crafted signature

(cherry picked from commit a97d1577057ae6623505560e836ca03f7ca5d3aa)

glv2/peerunity,peercoin/peercoin,DigitalPandacoin/pandacoin,DigitalPandacoin/pandacoin,DigitalPandacoin/pandacoin,ppcoin/ppcoin,glv2/peerunity,peercoin/peercoin,peercoin/peercoin,ppcoin/ppcoin,glv2/peerunity,DigitalPandacoin/pandacoin,peercoin/peercoin,peercoin/peercoin,peercoin/peercoin,ppcoin/ppcoin,ppcoin/ppcoin,DigitalPandacoin/pandacoin,glv2/peerunity,DigitalPandacoin/pandacoin