After loading the Fiesta challenge the rhme2 board(uart@19200bauds8N1) immediately output in loop "Lock" The aim of this challenge is to glitch the Clock or the VCC to exit this loop(skip jump instruction) and output the flag.
A very easy way to do this FI it is to plug HydraRHME2 with Chipwhisperer and configure Chipwhisperer Clock Out to 16MHz then power on the rhme2 board and just disconnect/reconnect the clock and by magic the flag appear ...
The real FI is to configure CWCapture with following parameters:
Scope Settings => Trigger Pins
Target IOI2 (Serial RXD)
Scope Settings => Glitch module
Clock Source CLKGEN
Glitch Width (as % of period) 20
Glitch Offset (as % of period) 30
Ext Trigger Offset 50000
Repeat 10
Glitch Explorer Window
Tuning Parameters 1
s.startswith("Lock")
s.find("FLAG")!=-1
Tuning Parameters 0
Param #0
['Glitch Module', 'Glitch Offset (as % of period)']
Float
Range -49, 30
Step 1
Repeat 1
