"Open Source" but not free to use as you wish. The Oracle builds require a commercial license.
Oracle also has their own build of the JDK which is not GPL. That is free to use in commercial software as well, under their "No-Fee Terms and Conditions"
For reference I double checked here: https://www.oracle.com/java/technologies/downloads/
https://blog.netwrix.com/2021/12/02/oracle-java-license-chan...
https://itassetalliance.com/blog-posts/what-do-oracles-2021-... says there was a change in 2019 that made critical security updates a paid feature.
The 2021 license change reverted this somewhat, by giving you one year of security fixes for free in the long term support versions (I’m sure I’m missing some detail, if not completely misinterpreting things, here)