Glossary
AWS access key
An access key ID and secret used to sign AWS API requests. AKIA prefixes are long-term IAM user keys; ASIA prefixes are temporary STS credentials.
An AWS access key is the pair of an access key ID and a secret
access key used to sign programmatic requests. The ID's prefix tells you
its kind: AKIA for a long-term key attached to an IAM user (or the root
user), ASIA for temporary credentials issued by STS, which also require
a session token and expire.
Long-term keys do not expire, which makes them the most common entry point
in AWS incidents when they leak into repositories, CI logs or images. In
CloudTrail, every signed call carries the key in
userIdentity.accessKeyId — the pivot for a
leaked access key investigation.
Reference: IAM unique ID prefixes.