In the next not yet released version 0.8.0 there will be a new option to disable a specific namespace type per sandbox. For example, disabling the network namespace would prevent this exploit.
This is more flexible than globally disabling all user namespaces as some programs might use other more harmless namespaces like Steam uses mount namespaces to setup runtime libraries.
https://github.com/igo95862/bubblejail
In the next not yet released version 0.8.0 there will be a new option to disable a specific namespace type per sandbox. For example, disabling the network namespace would prevent this exploit.
This is more flexible than globally disabling all user namespaces as some programs might use other more harmless namespaces like Steam uses mount namespaces to setup runtime libraries.