CloudBees CI version 2.504.3.28224 to 2.516.2.28983 can incorrectly clear artifacts and stashes

Issue

If "Artifact Management for Builds" is configured to use Amazon S3 cloud provider and Workspace Cache Manager is S3 Cache, then cache cleanup (which runs every 24 hours by default):

incorrectly deletes customer artifacts and stashes in the bucket (including caches from other controllers, or any data in the bucket path not generated by a cache step), as they are incorrectly identified as orphaned cache objects
causes increased CPU and memory consumption on the controller due to all objects in the S3 bucket are listed, instead of just cache objects

Evidence from logs:

Could not determine context ID for cache object '...', scheduling for deletion ...▼

Environment

CloudBees CI on modern cloud platforms - managed controller version 2.504.3.28224 to 2.516.2.28983, inclusive
CloudBees CI on traditional platforms - client controller version 2.504.3.28224 to 2.516.2.28983, inclusive
CloudBees Workspace Caching using AWS S3 cache implementation

Resolution

This issue is resolved in CloudBees CI version 2.516.2.28991.

Workaround

Navigate to Manage Jenkins System Workspace Caching. Temporarily switch from S3 Cache to None (disable caching). This will disable Workspace Caching, giving you time to plan the upgrade.

Tested product/plugin versions

CloudBees CI on traditional platforms - client controller version 2.516.2.28983
CloudBees S3 Cache plugin version 336