setuid() does not affect libuv's internal io_uring operations if initialized before the call to setuid(). This allows the process to perform privileged operations despite presumably having dropped such privileges through a call to setuid(). This vulnerability affects all users using version greater or equal than Node.js 18.18.0, Node.js 20.4.0 and Node.js 21.
The product performs an operation at a privilege level that is higher than the minimum level required, which creates new weaknesses or amplifies the consequences of other weaknesses.