The vulnerability, which affects Linux kernel versions 5.14 through 6.6, resides in the NF_tables, a kernel component enabling the Netfilter, which in turn facilitates a variety of network operations, including packet filtering, network address [and port] translation (NA[P]T), packet logging, userspace packet queueing, and other packet mangling. It was patched in January, but as the CISA advisory indicates, some production systems have yet to install it. At the time this Ars post went live, there were no known details about the active exploitation.