Clock attacks and power attacks are used as common means to inject faults in embedded devices. Critical analysis of the properties and the components engaged with these fault injection methods is of high importance to assess the related dangers and furthermore to enhance the process of designing suitable counter-measures. This paper provides critical analysis of induced faults on combinational and sequential circuits and study effects of various attacks (over-clock, under clock, power attack). While doing analysis, it was revealed that clock attacks i.e., under and over clock attacks have similarity index of (80–90%). Also it was found that power attacks have results similar (60–70%) to clock attacks but they cause propagation delay in circuits affecting the output. Cadence virtuoso 45 nm technology node, Keil and Multi-sim software’s were used to generate various attacks. The comparative analysis reveals that the attack timing and frequency of the glitch is the key while inducing fault injection attacks. While performing this work, it is observed the sequential circuits get less impacted by attacks comparing to combinational circuits. This research is conducted from an attacker’s perspective instead of mitigation perspective.