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Faaak 6 hours ago

Tinfoil hat mode: a competitor wants to exploit copy.fail on some ubuntu servers, and is DDoSing canonical so that they can't update and thus patch the vuln

yallpendantools 4 hours ago | parent | next [-]

Double tinfoil hat mode: an attacker learned of my plan to finally update my personal computer out of 20.04 today and is DDoSing canonical so I can't do that and I remain vulnerable to the backdoors they've found.

The plot thickens...

pixel_popping 2 hours ago | parent [-]

you are the center of all this, I knew it.

bjackman 4 hours ago | parent | prev | next [-]

If you can access AF_ALG on a server you don't need to do shenanigans like that. It's much easier to just find another bug and exploit that one instead.

The copy.fail website is very silly, it is not a special bug. If anyone gets compromised by that vuln their node architecture was broken anyway, patching copy.fail doesn't help.

loufe 3 hours ago | parent | next [-]

In what way is it "not a special bug"? It's a publicly known root access from RCE exploit. Those cannot be a dime a dozen. I'm sure it's especially interesting for any shared hosting services which might be affected, and could be delayed. I could find any places running containered services and exfiltrate secrets parallel services, no?

What constitutes "special" for you, out of curiosity? Something chaining with a hypervisor exploit?

bjackman an hour ago | parent | next [-]

It's not RCE it's an LPE in an obscure corner of the kernel attack surface that no sensible application depends on. They are absolutely a dime a dozen.

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).

2 hours ago | parent | prev [-]
[deleted]
mustardo 4 hours ago | parent | prev [-]

I thought copy.fail is a privelage escalation exploit, become root from a regular user? Am I missing something?

How would "node architecture" make people vulnerable to this?

You have to have shell access to a victim first right? Or am I missing something?

bjackman an hour ago | parent [-]

Yeah you need native code execution, and if you have AF_ALG access there is clearly no sandboxing in place. At that point it's game over on Linux, there are too many bugs. Even if you fix all the known ones in the current kernel, by the time the version with those fixes is qualified and released (not to mention, the machine must reboot), new LPEs have been discovered.

bouncycastle 5 hours ago | parent | prev | next [-]

Seems reasonable to assume it's something to do with the recently publicized exploits. More likely, this could be an extortion attempt by criminals rather than a competitor.

kubb 5 hours ago | parent | prev | next [-]

s/competitor/intelligence services/

ramon156 2 hours ago | parent [-]

+1, it hasnt even been 24 hours and I already see these stupid CyberSec companies trying to squeeze themselves between this.

touwer 4 hours ago | parent | prev [-]

why a competitor? Criminals, secret services, country adversaries...