It appears there has been a noticed exploit vulnerability in Linux Kernels v5.14 up to v6.6. The exploit seems to be a “privilege escalation from unprivileged user to root user. And, it should be noted that the exploit can read/write any physical memory on the device, but uses it to become root user. An important note is that the exploit requires nf_tables to be present, and unprivileged user namespaces. This can be checked with commands specified in the README.md file in the repo.”

You can read more about this and the context/background of the exploit at the following link:
https://pwning.tech/nftables/

It is highly recommended to update your kernel as it seems this was patched in February. To check which kernel you have, simply type hostnamectl and check the Kernel heading: