A thousand fewer paths to root

All software is Swiss cheese to smart enough AI, and unless you can provably create secure software - you never really can. Breaking it just requires more intelligence than the thing securing it.

It's a good reason why we may need to borderline shutdown the internet in the future because to a super intelligent AI, there are no barriers. Everything is essentially open. It creates its own zero day exploits as it goes.

Because the large corporations that fund Linux development and use Linux value speed over security.

Speed requires a lot of code in the kernel, where that code can run fast.

There are kernels that do not have a thousand privilege escalation exploits. These kernels are smaller and much easier to check for bugs. But those kernels are significantly slower.

For many use cases, slower is not a problem. But for the large corporations who fund a lot of Linux development and use Linux in large data centers, every 1% slower can literally be millions of dollars worth of additional servers that are required.

OpenBSD shows that you can have a Unix security model without a thousand privilege escalation exploits. But OpenBSD is like 10% slower. So corporations won't use it because it would cost millions of dollars more per year and some of their software requires access that OpenBSD does not grant precisely because that access leads to security exploits (i.e. io_uring, eBPF etc. etc.)

You could also use like seL4, but that's slow too

So that's why. It's a business tradeoff between cost of servers vs cost of getting hacked, and cost of servers wins.

Many people seem to be making this about their pet issue, but "these systems are complex" and "the frontier labs have developed models that are superhuman at hacking" seems like a totally sufficient explanation.

I've been working with a LoRa chip called the LR2021. I plugged a dev board into my computer and told Claude to reverse engineer it. He dissected it with a speed and level of efficiency I couldn't believe. Within a few hours, Claude was writing custom patches for a completely opaque patch RAM area meant only for the manufacture. I wrote about it here: https://beala.substack.com/p/your-node-doesnt-need-a-microco...

> Should we assume that all software is more compromised than the kernel?

Absolutely, the front door has always been unlocked. We were previously protected by the economics of exploit detection favoring the developers, but now we have entered a new world.

The issues arise almost everywhere we look. It's frustrating because the user experience in edge systems has barely changed in the last fifteen years. We could have rode the advances in semiconductor manufacturing to embed more layers of protection such as CHERI while slightly slowing down the rate of performance improvements. Instead we have only marginally upgraded security and largely added features which the users scarcely notice.

I am hopeful about the long term prospects of formal verification, but having humans reviewing the proof statements and confirming they match our desired properties will take many years. Meanwhile, AI assisted hacking is an urgent issue. So we will have to delegate implementation, proof specification, and proof development to the AIs in the short term. Maybe that goes well, but who knows. Interesting times.

For all of my time being aware of this industry, it has generally been understood that privilege escalation bugs are common. This has always been a thing. A lot of people say, commonly and for many years, that if your security depends on there not being privilege escalation bugs, you don't have security.

The dirty secret is multi-user died in the 90s and privilege escalation has basically been considered table-stakes since then.

Yes, you should assume that all software you use is full of holes, and after we patch all the holes that could conceptually have been discovered by a motivated human, there will still be holes that can only be found by considering larger windows of context than any human has or could. Even when something is formally verified, that doesn't extend to its software environment or the hardware it's running on, and those can introduce exploitable vulnerabilities as well. You can only ever be very confident that we've found all the holes at a given analysis capability level -- if something a hundred times as capable looks, it will likely find many more. That's how it will be.

>Is the kernel simply too complex to reason about? Is it an underlying flaw in the security model or language implementation?

There is nothing magical about kernel. Look at the code anywhere and it has bugs, lots of them.

Security bugs are just bugs. More often than not they are silently there and don't prevent you from using the software and you can't react and fix them because of that.

Give it time and they accumulate

Have you written a kernel? Even toy kernels are hard to make without vulnerabilities.

Human brain mostly take the shortest available path for a solution to reduce the cognitive load. When a system complexity increases probability of cutting the corners will get increased. This is a known pattern. Models just do the polar opposite. They try to cover almost every hypothetical edge cases. They never get tired or bored, nor do they suffer from glucose limits, mental fatigue, or shifting attention spans, which is one cause of over engineering, but valuable in vulnerability tracing.

> How did we get to the point where there are a thousand privilege escalation exploits in the kernel?

it's been rule of thumb basically forever that there is 1 bug per ~10KLOC for any project

linux kernel is millions of lines, so thousands of bugs being hidden there is about on point

(tho obviously far smaller serious escalation ones, obviously, but you're exaggerating as well)

How can it be surprising that a software made from 40+ million lines of memory-unsafe code has hundreds of critical bugs?

Software really is that complicated.

The Linux kernel is simply not good quality code.

AI helps find vulnerabilities, but the way things are written were already fertile ground.

The kernel has the problem that basically every bug in it is also a security vulnerability. All software has bugs. Had Linux been written in Rust, and I strongly recommend a rewrite, it would still have bugs, and thus would still have vulnerabilities. But they'd be way less.

I recall reading that every IBM mainframe OS release had 1000 bugs in it. (This was in the 1970s/80s.) Sorry I can't supply a source, after 4-5 decades. It was probably an article in Datamation magazine.

Now, I don't know how many of those bugs were privilege escalations, or could be leveraged to be. I'm not sure that people tried to exploit in the same way back then (or, if they did, if they said anything publicly about the results). Still, even if the majority of those bugs were not exploitable, OSes were much smaller then.

So that's my conclusion of how we got here: We've always been here.

> How did we get to the point where there are a thousand privilege escalation exploits in the kernel?

We developed AIs that can find them.

amazing things happen when you decide that device drivers should be a part of your kernel codebase

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As models get more advanced and generate an increasing throughput of increasingly higher quality results, how are you determining when to trust its results and when human review is needed on what?

E.g., 948 results is a high number to review in a timely manner unless your team is very large or spending several months combing through the results

EDIT: nvm i shouldve kept reading, answered

> At this scale, manually investigating every report is impractical for our research team. We therefore focused on validating findings that a) were reachable by a low-privileged user, b) required no special capabilities, and c) produced measurable evidence of memory corruption.

It's a bittersweet result, like finding asbestos in your house. I'd rather know than not, but I would much prefer not having it in the first place.

I understand this work was based on a dated snapshot. Will there be any continuous effort, scanning new PRs as they land, to prevent new weaknesses from being added?

Thanks. I'm not a programmer so I can't understand what is happening in the kernel by looking at the changelog, so I'll ask: Are the problems remediated structurally so that nothing like it can occur in the future, rather than just patching it up? Are there "lessons learned" that are being applied and documented here (like, "this problem looks like it's shape transports to other subsystems as well, let's fix them all in a disciplined way")?

I'm going to assume that there was "old" code that caused LPE vulnerabilities, but, The Linux Foundation have their own project Sashiko (https://sashiko.dev/), which analyzes each commit to the Linux Kernel for bugs and vulnerabilities using Googles models, my question is then, how many of the vulnerabilities you found were also caught by Sashiko?

I'd like to see a break down by age of code and part of kernel (drivers, networking, core ,etc ..)

The high number is really impression to the point of making me skeptic. Are these distinct vulnerabilities or are a lot of the related in the way vulns often are?

The article says "The target virtual machines ran a stock desktop operating system". Are the vulns in the kernel specifically or does this include software running as root?

I wish these blog posts included statistics on the categories of deficiencies that cause these vulnerabilities, and proposed measures to avoid them

A system that admits THOUSANDS of such vulnerabilities is certainly flawed in several fundamental aspects

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In general computer systems have been known unreliable since the 1980s, especially when networked. The entire cyber security industry operates not by preventing intrusions in the first place, but by rapidly mitigating them when they inevitably happen.

Hopefully this type of work to automatically discover & patch vulnerability leads to much more reliable software, and the remove the need for cyber security.

Just in the last month multiple governments had to shut down important online services due to a PHP vulnerability, and seven EU countries have had disruption to their food supply after millions of dollars' worth of it was cooked in hacked fridges. We aren't at existential yet, but we seem to be getting there.

The governments buy them up [1]. Nukes wouldn't be required for WW3.

[1] https://www.cyberdefensemagazine.com/zero-day-market-the-gov...

Because critical systems are mostly not accessible from the open internet

Cybersecurity operates under the "not enough bears" theory of security. There are a million people in a valley and a male and female bear. You do not need to outrun the bears, you just need to outrun the two slowest people. Next year there are more bears, but you still only need to outrun a few people. Then, one day, there are a million bears and they eat you all. But that day has not happened yet.

To explain more seriously, almost all visible cyberattacks are carried out by profit-motivated criminals. This has a very clear cost-benefit analysis; your revenue is hacking organizations and extorting them for available money, and your costs are developing and deploying attacks. The ROI is outrageously good easily being on the order of 10x to 100x. If it is so easy and so profitable why do not they just hack all of the millions of organizations on the planet with millions of dollars of available cash for trillions of dollars of revenue? Sure, all they have to do is create a trillion dollar revenue commercial organization bootstrapping themselves with no outside investors, loans, or access to financial resources or the financial system.

I mean, it took Mark Zuckerberg 20 years and a metric ton of VC investment and public investment to make 200 billion dollars in revenue. So what kind of loser can not make a commercial organization 5x larger with a trillion dollars in revenue in less time with no outside investors? Are they even trying? Just make more revenue than any other commercial organization in the entire world and extract that money in a freely usable form, how hard can that be?

They are not there yet, but they are trying. If you look at cybercrime reports you see something like 3x-10x growth year over year. Ransomware reports from a few years ago were showing a 3x year over year growth in number of attacks and simultaneously a 3x year over year growth in ransom amount with the averages being on the order of 100,000 dollars. Chump change for any serious organization, but give that a few years of 3x and that starts to look like real money. However, as it becomes real money it becomes harder and harder to launder it into a usable form. Sure, you could hit someone for 30 million dollars, but how are you going to get that into your bank account? Cryptocurrency helps some, but even there the big money tries to steer away from large overt crime. Maybe you could launder a few tens of billions a year that way, but that is still a far cry from the trillions for everything everywhere.

And of course even assuming you can scale your organization 10x year over year it still takes a decade of sustained growth, scaling your hiring and organization across 9 orders of magnitude, to get to billions per year. A literal decade even if you were growing at a outrageous pace for a outrageous amount of time just to reach a fraction of the total addressable market. A decade of that and you are still nowhere near blowing up all the power plants. Give it time, we need a lot of bears to get there.

Linux has effectively same options and more via LSM. I'm not sure why ACL is mentioned here since it exists on Linux too. What advantage do you mean specifically?

There are a lot of LPE's in Windows too. Remember that it started out as a single user operating system, it took a long time to get software on board to not always running as admin.

LPEs are frequent enough that people no longer use low-privilege user accounts to sandbox potentially malicious software. They are only used to control access for well-behaved users without any intent to subvert the system, not attackers.

The difference here reminds me of the distinction between the regular Paxos algorithm and the Byzantine Paxos algorithm.

This has been true for DECADES.

Regular LPEs are not novel. The frequency has just increased a lot.

This, but for anything Capital-gated. Imagine if all universities could get access to radiotelescope time, atom smasher time, quantum compute research lab access... frontier models on massive datacenters represents a huge new category of captured commons.

Anthropic ran Mythos against OpenBSD and only had 1 reported vulnerability.

https://www.anthropic.com/glasswing

Oh no, they will not be secured against their own users :(