Permission denied - Failed to rexec as memfd

[ghost]

Platform: ChromeOS Flex
Version: 108.0.5359.111

Output:
lxc-attach
Permission denied - Failed to rexec as memfd
Failed to re-execute lxc-attach via memory file descriptor

I understand that this tool was originally built for brunch but could you at least point me the direction at which i need to look? Is it a kernel configuration? Because when I checked my kconfig, the only option mentioning memfd was already enabled. I can't see what regular ChromeOS has that ChromeOS Flex lacks.