In 2020, Constella Intelligence’s threat intelligence team detected over 8,500 breaches and leakages circulating in dark markets and underground forums, representing nearly 12 billion records. Constella analyzed a significant portion of the breaches and leakages detected in underground marketplaces in 2020, constituting a 32% increase in the total volume of breaches and leakages analyzed in 2019. Constella’s 2021 Breach Report offers insights into these cyber threats and the impact of malign activities fueled by breach data circulating on the deep and dark web.