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NT OS Kernel Information Disclosure Vulnerability

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Re: NT OS Kernel Information Disclosure Vulnerability

#11
post #3

I went to check when the bug had been patched, and was left wanting. I however lack the expertise to really appreciate how much danger exists in practice, or for whom. I just know I do have Win11 24H2 and "This leak primitive is particularly useful for Windows versions 24H2 or later"

This type of exploit is useful as part of a chain of exploits; it defeats a defense-in-depth protection.

Specifically, it leaks a kernel address inside a security-sensitive structure, which is supposed to be unpredictable / unknowable because the layout of kernel memory is randomized.

If you have another exploit that will write bytes under the attacker’s control to an attacker-supplied kernel address, you will be able to do the Windows equivalent of escalate to root.

Re: NT OS Kernel Information Disclosure Vulnerability

#12
post #9

I find myself thinking "wow, what an obvious bug. How did Microsoft not catch that?" but then I think back to some of my own extremely obvious bugs. Thankfully my code is much lower impact.

I still think of the lessons learned from a root traverse bug I accidentally coded into one of our internal apps as a jr dev. You could change the URL of the image, and get any file off the system to download as long as the service account had read access. Invaluable XP, and really glad everything was behind AD authentication and internal users were trustworthy enough and operating in a network isolated context.

Yeah, having learnt very similar (if not the same) lessons myself the hard way I see great value in being able to fail badly, but with low stakes. I catch loads of bugs like these from jrs before they hit prod but I don't feel like they're learning the fundamentals of security like trust, sanitising inputs, least privilege etc.

Re: NT OS Kernel Information Disclosure Vulnerability

#13
post #10

Random: Perhaps that full source code leak in 2004 actually helped harden the kernel, long term? https://betanews.com/2004/02/13/windows-source-leak-traces-b...

KASLR was not present in Windows 2000, which is what this vulnerability breaks through.

Re: NT OS Kernel Information Disclosure Vulnerability

#14
post #5
post #3

I went to check when the bug had been patched, and was left wanting. I however lack the expertise to really appreciate how much danger exists in practice, or for whom. I just know I do have Win11 24H2 and "This leak primitive is particularly useful for Windows versions 24H2 or later"

If you follow the CVE link included: https://msrc.microsoft.com/update-guide/vulnerability/CVE-20... It would seem this was patched in the Aug 12 security patch rollout.

Wow thanks! I didn't even realize that was a link, it looks like just any other bold text in the page. It's weird this page would be published in Sept (if I understand correctly) and not mention the patch, but in any case that's good.

Re: NT OS Kernel Information Disclosure Vulnerability

#15
post #13
post #10

Random: Perhaps that full source code leak in 2004 actually helped harden the kernel, long term? https://betanews.com/2004/02/13/windows-source-leak-traces-b...

KASLR was not present in Windows 2000, which is what this vulnerability breaks through.

That’s one vulnerability.

Re: NT OS Kernel Information Disclosure Vulnerability

#17
post #9

I find myself thinking "wow, what an obvious bug. How did Microsoft not catch that?" but then I think back to some of my own extremely obvious bugs. Thankfully my code is much lower impact.

I still think of the lessons learned from a root traverse bug I accidentally coded into one of our internal apps as a jr dev. You could change the URL of the image, and get any file off the system to download as long as the service account had read access. Invaluable XP, and really glad everything was behind AD authentication and internal users were trustworthy enough and operating in a network isolated context.

sounds like how wordpress used to be. could explore all the folders and get any file of site with something like website.com/content/2010/

Re: NT OS Kernel Information Disclosure Vulnerability

#18

It’s interesting that the KB that patches this on Windows 11 (KB5063878) is the same one that was tied up in all the Phison SSD drama.

1) Those patches address a wide range of issues, from bug fixes to feature additions, to security fixes. This is uninteresting.

2) The issue had nothing to do with the patch. It was a coincidence.

Re: NT OS Kernel Information Disclosure Vulnerability

#19
post #15
post #13

Earlier quoted context omitted.

KASLR was not present in Windows 2000, which is what this vulnerability breaks through.

That’s one vulnerability.

Lol yep.

I mean, it wasn't like the address space was all that large back then, anyhow.

Re: NT OS Kernel Information Disclosure Vulnerability

#20
KASLR is broken anyway, at least on x86, even with KPTI (a Linux feature to mitigate Meltdown) enabled. See https://www.willsroot.io/2022/12/entrybleed.html, which still runs fine (with some modifications depending on the microarchitecture) on the latest AMD and Intel hardware that we've checked.
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