Breach and Attack Simulation vs External Attack Surface Management

The BAS and EASM space seems to be getting muddier and muddier. When I talk to security professionals, they all seem to have their own definition of these terms and don't know which one provides more value as they are still relatively new. Some organizations choose BAS over EASM, while others choose EASM over BAS. What is your thought on this topic? What decisions your organizations made in the past and why?

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