We have recently been made aware of another root exploit found in the Linux kernel. We have verified the PoC on a server running Ubuntu 24.04 and 6.8.0-111.
https://github.com/V4bel/dirtyfrag/tree/master
This is very new and was disclosed earlier than planned so there is no kernel patch and we're potentially a long way from an updated kernel package being released by Ubuntu.
The mitigation suggested at the above url appears to work and I would recommend applying it to all servers immediately. It will break IPsec and AFS (distributed file system). If you're not familiar with those technologies, you are not using them.
From the above link:
sh -c "printf 'install esp4 /bin/false\ninstall esp6 /bin/false\ninstall rxrpc /bin/false\n' > /etc/modprobe.d/dirtyfrag.conf; rmmod esp4 esp6 rxrpc 2>/dev/null; true"
I would suggest to reboot after applying the mitigation if possible.
