An AWS IAM access key is a programmatic credential used to authenticate requests to AWS services through the CLI, SDKs, APIs, or automation tools. In practice, it is part of a key pair: an access key ID and a secret access key. Together, they let an application or script prove which IAM identity is making the request.
This matters because anyone who steals a valid access key can often use AWS as if they were the real operator, limited only by that identity’s permissions. Attackers abuse leaked keys to create resources, read data, change access, or drive up bills with cloud and AI services. Defenders reduce risk by avoiding long-lived keys where possible, using temporary role credentials, rotating and revoking exposed keys quickly, enforcing least privilege, and monitoring CloudTrail and billing for unusual API activity.