… worse, but are not in themselves the main issue with sudo.
SUID processes are weird concepts: they are invoked by unprivileged code and inherit the execution context intended for and controlled by unprivileged code. By execution context I mean the myriad of properties that a process has on Linux these days, from environment variables, process scheduling properties, cgroup assignments, security contexts, file descriptors passed, and so on and so on. A few of these settings the kernel is nice…
… enough to clean up automatically when a SUID binary is invoked, but much of it has to be cleaned up by the invoked suid binary. This has to be done very very carefully, and history has shown that SUID binaries are generally pretty shit at that.
So, in my ideal world, we'd have an OS entirely without SUID. Let's throw out the concept of SUID on the dump of UNIX' bad ideas. An execution context for privileged code that is half under the control of unprivileged code and that needs careful, …