Spinnaker: RCE via expression parsing due to unrestricted context handling

Spinnaker is an open source, multi-cloud continuous delivery platform. Echo like some other services, uses SPeL (Spring Expression Language) to process information - specifically around expected artifacts. In versions prior to 2026.1.0, 2026.0.1, 2025.4.2, and 2025.3.2, unlike orca, it was NOT restricting that context to a set of trusted classes, but allowing FULL JVM access. This enabled a user to use arbitrary java classes which allow deep access to the system. This enabled the ability to invoke commands, access files, etc. Versions 2026.1.0, 2026.0.1, 2025.4.2, and 2025.3.2 contain a patch. As a workaround, disable echo entirely.