What is _iokstg_ on my keychain?

Add on

Per Apple, the file-based keychains are fading away, with a migration to the data protection keychain underway. (Which can use biometrics and the secure enclave, where the file-based keychains cannot.)

Related: TN3137: On Mac keychain APIs and implementations | Apple Developer Documentation

TN3137 contains the following statement: "The file-based keychain is on the road to deprecation. It’s not officially deprecated, but some of the APIs surrounding it are. For example, SecKeychainCreate was deprecated in the macOS 12 SDK. Moreover, new features, like iCloud Keychain, require the data protection keychain."

https://forums.macrumors.com/threads/something-odd-in-keychain-hacked.2178704/

Beyond that I have no ideas

Perhaps some else will pick this up ?

Does this " issue " relate to where your question is posted macOS 14 Sonoma ?

Or, does it relate to " iMac 24″, macOS 15.3 " Sequoia ?

Perhaps and in either case

A Screen Shot of where and what you are seeing may help

Just be sure Not to Included any personal information in that image