.ISDATA File Extension

MacOS stores ISDATA files in the following directory:

Macintosh HD/​Library/​Caches/​com.apple.iconservices.store

Typically, users cannot access this directory (to prevent them from accidentally moving, modifying, or deleting system files). If you do access the com.apple.iconservices.store directory, you will likely find thousands of ISDATA files.

Are ISDATA files malware?

ISDATA files stored in the com.apple.iconservices.store directory are not malware. They are legitimate system files that macOS uses to load icons more quickly.