Firecracker is open source and possibly others use it, AWS sells services with it though.
It has notable adoption in the agent sandbox space where this type of vulnerability is especially volatile.
> The target was Firecracker v1.16.1 on x86-64, with host kernel 7.0.0-1011-aws.
[dead]
(A more complete way to say this is that Firecracker is the engine built to run AWS Lambda and AWS Fargate).