Break IC, Recover MCU, Microcontroller Reverse Engineering

Clock-signal glitches are currently the simplest and most practical ones. In real application glitches are normally used to replace conditional jump instructions and test instructions preceding them. They create a window of vulnerability in the processing stages of many security cryptographic barriers by simply preventing the execution of the code that detects an unsuccessful authentication attempt. Instruction glitches can also be used to extend the runtime of loops, for example, in serial port output routines to see more of the memory after the output buffer, or to reduce the number of loops in cryptographic operation to transform the cipher into a weak one.

To perform a glitch, the clock frequency should be temporarily increased for one or more half cycles so that some flip-flops sample their input before the new state has reached them. As clock glitches are normally aimed at CPU instruction flow, they are not very effective for devices with hardware implementations of security protection. Therefore it is practical to use clock glitches only when attacking microcontrollers with software programming interfaces or some smartcards.

We can break atmel avr mcu ATMEGA8535L heximal, please view the atmel avr mcu ATMEGA8535L features for your reference:
The ATmega8535 provides all the features of the ATmega8535L. In addition, several new features are added. The ATmega8535 is backward compatible with ATmega8535L in most cases. However, some incompatibilities between the two atmel avr mcus exist.

To solve this problem, an ATmega8535L compatibility mode can be selected by programming the S8535C fuse. ATmega8535 is pin compatible with ATmega8535L, and can replace the AT90S8535 on current Printed Circuit Boards. However, the location of fuse bits and the electrical characteristics differs between the two devices.

Port A serves as the analog inputs to the A/D Converter. Port A also serves as an 8-bit bi-directional I/O port, if the A/D Converter is not used. Port pins can provide internal pull-up resistors (selected for each bit). The Port A output buffers have symmetrical drive characteristics with both high sink and source capability before break atmel avr mcu.
When pins PA0 to PA7 are used as inputs and are externally pulled low, they will source current if the internal pull-up resistors are activated.

The Port A pins are tri-stated when a reset condition becomes active, even if the clock is not running. Port B is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The Port B output buffers have symmetrical drive characteristics with both high sink and source capability after Break Atmel AVR MCU ATmega8535L Heximal.
As inputs, Port B pins that are externally pulled low will source current if the pull-up resistors are activated. The Port B pins are tri-stated when a reset condition becomes active, even if the clock is not running. Port C is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The Port C output buffers have symmetrical drive characteristics with both high sink and source capability.

As inputs, Port C pins that are externally pulled low will source current if the pull-up resistors are activated. The Port C pins are tri-stated when a reset condition becomes active, even if the clock is not running. Port D is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The Port D output buffers have symmetrical drive characteristics with both high sink and source capability when Break Atmel AVR MCU ATmega8535L Heximal.
As inputs, Port D pins that are externally pulled low will source current if the pull-up resistors are activated. The Port D pins are tri-stated when a reset condition becomes active, even if the clock is not running before break IC.

We can recover atmel avr controller ATMEGA48V firmware, please view the atmel avr controller ATMEGA48V features for your reference:

Port B is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The Port B output buffers have symmetrical drive characteristics with both high sink and source capability. As inputs, Port B pins that are externally pulled low will source current if the pull-up resistors are activated. The Port B pins are tri-stated when a reset condition becomes active, even if the clock is not running.
Depending on the clock selection fuse settings, PB6 can be used as input to the inverting Oscillator amplifier and input to the internal clock operating circuit. Depending on the clock selection fuse settings, PB7 can be used as output from the inverting Oscillator amplifier.
If the Internal Calibrated RC Oscillator is used as chip clock source, PB7..6 is used as TOSC2..1 input for the Asynchronous Timer/Counter2 if the AS2 bit in ASSR is set before Recover Atmel AVR Controller ATmega48V Firmware.
Port C is a 7-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The PC5..0 output buffers have symmetrical drive characteristics with both high sink and source capability. As inputs, Port C pins that are externally pulled low will source current if the pull-up resistors are activated. The Port C pins are tri-stated when a reset condition becomes active, even if the clock is not running.
If the RSTDISBL Fuse is firmwaremed, PC6 is used as an I/O pin. Note that the electrical characteristics of PC6 differ from those of the other pins of Port C. If the RSTDISBL Fuse is unfirmwaremed, PC6 is used as a Reset input. A low level on this pin for longer than the minimum pulse length will generate a Reset, even if the clock is not running if Recover Atmel AVR Controller ATmega48V Firmware.
Port D is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The Port D output buffers have symmetrical drive characteristics with both high sink and source capability. As inputs, Port D pins that are externally pulled low will source current if the pull-up resistors are activated. The Port D pins are tri-stated when a reset condition becomes active, even if the clock is not running.
AVCC is the supply voltage pin for the A/D Converter, PC3:0, and ADC7:6. It should be externally connected to VCC, even if the ADC is not used. If the ADC is used, it should be connected to VCC through a low-pass filter. Note that PC6..4 use digital supply voltage, VCC before Recover Atmel AVR Controller ATmega48V Firmware.
In the TQFP and QFN/MLF package, ADC7:6 serve as analog inputs to the A/D converter. These pins are powered from the analog supply and serve as 10-bit ADC channels. The ATmega48V is a low-power CMOS 8-bit atmel avr controller based on the AVR enhanced RISC architecture.
By executing powerful instructions in a single clock cycle, the ATmega48/88/168 achieves throughputs approaching 1 MIPS per MHz allowing the system designer to optimize power consumption versus processing speed if RECOVER MCU.

Every transistor and its connection paths acts like an RC element with a characteristic time delay. The maximum usable clock frequency of a processor is determined by the maximum delay among its elements. Similarly, every flip-flop has a characteristic time window (of a few picoseconds) during which it samples its input voltage and changes its output accordingly. This window can be anywhere inside the specified setup cycle of the flip-flop, but is quite fixed for an individual device at a given voltage and temperature. So if we apply a clock glitch (a clock pulse much shorter than normal) or a power glitch (a rapid transient in supply voltage) this will affect only some transistors in the chip and cause one or more flip-flops to adopt the wrong state. By varying the parameters, the CPU can be made to execute a number of completely different wrong instructions, sometimes including instructions that are not even supported by the microcode. Although we do not know in advance which glitch will cause which wrong instruction in which chip, it can be fairly simple to conduct a systematic search.

IC break Methods

IC break can be diversify as three different ways like semi-invasive break IC, un-invasive IC break, invasive break IC. And ultra-violet radiation break IC is the most ancient way of this industry. In the middle of 1970 attacker use this way to IC break and it has been viewed as the invasive attack, but it need to decapsulate the package of IC, and surely it will classify semi-invasive IC break. But it works on most of the OTP and UV EPROM microcontrollers. These MCU IC can fend off the low cost and low level IC break.
Ultra-Violet IC break can be separated into two steps: the first one is locate the security fuse of IC, and then use ultra-violet radiation to reset the IC to un-protection states. Normally the design of security fuse in the IC later than IC memorizer but ultra-violet radiation can cover the whole IC.
Circuit Engineering Company Limited continues to be recognized as the Southern China Leader in Services for IC breakion service. With the advancement of today’s modern circuit board technology, it is more important than ever to have specialists available to help you at a moment’s notice. Our engineering and commercial teams collectively have a vast amount of electronic experience covering field include Consumer Electronics, Industrial Automation Electronics, Wireless Communication Electronics., etc. For more information please contact us through email.

Glitch attacks are fast changes in the signals supplied to the device and designed to affect its normal operation. Usually glitches are inserted in power supply and clock signals, but a glitch could be an external electric field transient or an electro-magnetic pulse. two metal needles might be placed on a smartcard within a few hundred micrometers away from the chip surface. Then by applying a spike of a few hundred volts for less than a microsecond on these needles, an electric field in the silicon substrate of sufficient strength to temporarily shift the threshold voltages of nearby transistors will be induced. One modification of the above proposal was suggested recently: using a miniature inductor consisting of several hundred turns of fine wire around the tip of a microprobe needle. A current injected into this coil will create a magnetic field, and the needle will concentrate the field lines.

Power consumption characteristics always include noise components. The external noise can be reduced by proper design of the signal acquisition path and careful use of the measurement equipment. Measuring the power consumption on the resistor in the ground line has some advantages. Firstly, it reduces the noise level and, secondly, it allows us to measure the signal directly with an oscilloscope probe, because most probes have their common line permanently connected to the main power ground. To increase the signal-to-noise ratio further, the number of averaged samples can be increased.

The various instructions cause different levels of activity in the instruction decoder and arithmetic units, and can often be quite clearly distinguished so that parts of algorithms can be reconstructed. Various units of the processor have their switching transients at different times relative to the clock edges, and can be separated in high-frequency measurements.

There are many publications on different power analysis techniques that can be used to break many cryptographic algorithms. The whole process of analysis is relatively easy to implement, and only requires standard off-the-shelf measurement equipment costing a few thousand pounds.