What constitutes "special" for you, out of curiosity? Something chaining with a hypervisor exploit?
Even just in AF_ALG there have been several such vulns fixed in 2026 already. Kernel wide probably hundreds. It's true that most of them will be harder to exploit than this one but that just means you need to prompt your AI a bit harder to get an exploit. (To be fair, in a lot of cases it's gonna be hard to escalate privs without crashing the machine).
Ubuntu has userns restrictions now which takes away the main sources of LPEs (random qdiscs, nftables, all that garbage) but there are still huge numbers of these vulns. This is why platforms that do native untrusted code executions have extreme sandboxing. Note Android and ChromeOS aren't affected coz they already knew this code was broken and hide it from unpriv workloads.
You can't run untrusted code on Linux without either a very very carefully designed sandboxing layer (like Android/ChromeOS) or virtualization. copy.fail is just one among tens of thousands of reasons for this, and it's a pretty uninteresting one at that.
What is "special" depends on your usecase but for my job it's mostly about stuff that's exposed to KVM guests. Biggest source of concerning vulns for us is probably vhost. I expect there are also lots of undiscovered and scary vulns in places like virtiofs, vfio, DAX, and wherever we do device passthrough.
> I could find any places running containered services and exfiltrate secrets parallel services, no?
Yes. Regardless of copy.fail. Cloud providers don't do that without a VM layer. (If yours does, you need to switch).
Also even if it's not strong, it doesn't mean it's entirely worthless. You can't rely on it, but it's usually free and it still buys you time / increases attack cost.
Like, if you leave 100k cash in a car on the street in SF, that's dumb. If you really need to do that for some strange reason, you should hire a security guard to watch your car, because cars a not a good security boundary. BUT, that doesn't mean you would leave the car unlocked just coz someone's watching it!
Clouds use VMs as the security barrier, which is also not always 100% perfect, but is much better.
It could be useful as part of an exploit chain but generally once you've got to local code execution it's not going to be difficult to get further.
A "special" bug would be something that defeats a security barrier that people actually use, e.g. something that works remotely, or as you say - a hypervisor hack.