An IAM execution role is the AWS identity that an application, service, or workload assumes to access resources and call APIs. Instead of embedding static keys, the runtime receives temporary permissions tied to that role. Those permissions define what the code can do: read storage, invoke services, write logs, or reach other cloud resources.
This matters because the role becomes part of the attack surface. If an attacker can influence the workload, exploit a misconfiguration, or abuse metadata access, they may use the role’s temporary credentials to act with the workload’s privileges. In cloud defenses, the main controls are least privilege, short-lived credentials, tight trust policies, and clear separation between user input and cloud actions. In agentic systems, an execution role that is too broad can turn a small compromise into a wider cloud incident.