Meltdown Proof-of-Concept

Re:Meltdown Proof-of-Concept by john_teller02 on Tuesday January 09, 2018 @12:40PM (#16107995)

These two bugs (Meltdown and Spectr) are really very speculative things. It is like when human beings became aware of astroid orbits they thought that earth is in danger of being hit by one. Now that is indeed a theoritical possibility but what are the chances? These two bugs have been existent for 20 years and there is no known exploits of them. In the GitHub demos also they mention that the demos will work only if "For this demo, you either need the direct physical map offset (e.g. from demo #2) or you have to disable KASLR by specifying nokaslr in your kernel command line." - So you basically start with a broken system to exploit these bugs.

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Re:Meltdown Proof-of-Concept by firethief on Tuesday January 09, 2018 @01:13PM (#16108294)

This is literally a PoC. It's too late for the standard "I can't imagine how to exploit this so surely it cannot be done" fallacy. You are looking at an example of how to do it.

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Re:Meltdown Proof-of-Concept by hannasanarion on Tuesday January 09, 2018 @12:51PM (#16108085)

If you don't know the difference between the existence of an earthbound asteroid and the existence of people who write computer viruses, I don't know what to tell you.

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Re:Meltdown Proof-of-Concept by odonnellryan on Tuesday January 09, 2018 @01:55PM (#16108685)

What's the name for this logical fallacy? You see this shit all the time.

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Re:Meltdown Proof-of-Concept by tedunangst on Tuesday January 09, 2018 @03:13PM (#16109541)

I like false equivocation.

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Re:Meltdown Proof-of-Concept by anarazel on Tuesday January 09, 2018 @03:11PM (#16109524)

"Bullshitting"?

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Re:Meltdown Proof-of-Concept by Skunkleton on Tuesday January 09, 2018 @03:38PM (#16109813)

Its like circular logic on steroids. Parent is using the word "speculative" to discredit the vulnerabilities that use speculative execution.

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Re:Meltdown Proof-of-Concept by mark-wagner on Tuesday January 09, 2018 @02:45PM (#16109204)

Probably false analogy.

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Re:Meltdown Proof-of-Concept by andylei on Tuesday January 09, 2018 @01:24PM (#16108424)

> For this demo, you either need the direct physical map offset (e.g. from demo #2)

as in, demo #2 is a working exploit to get this map

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Re:Meltdown Proof-of-Concept by dsfyu404ed on Tuesday January 09, 2018 @12:45PM (#16108035)

>These two bugs have been existent for 20 years and there is no known exploits of them.

They don't exactly leave behind a lot of telltale signs.

This is also the kind of bug that is so broad (read access to everything on almost any machine you can execute code on) that a large subset of those equipped to discover it would have kept their mouths shut.

> So you basically start with a broken system to exploit these bugs.

A lot of systems were broken in the time before KASLR came along

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Re:Meltdown Proof-of-Concept by voidmain on Tuesday January 09, 2018 @12:46PM (#16108049)

Attacks are not asteroids: attackers constantly improve them to bypass improved defenses, and the "improbability" of an attack is no defense. Bypassing KASLR with these attacks is easy and real attackers will do it.

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Re:Meltdown Proof-of-Concept by abritinthebay on Tuesday January 09, 2018 @01:27PM (#16108453)

I think you're being harshly down-voted without people explaining why.

For a start - this is hardly a remote possibility when we already have proof of concepts like the linked repo.

Secondly - your analogy makes no sense. The only way to make it make sense is add that we also know there is an entire spacefaring group of mercenaries whose entire hobby and/or job is deliberately throwing asteroids in Earths general direction.

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Re:Meltdown Proof-of-Concept by Skunkleton on Tuesday January 09, 2018 @03:39PM (#16109824)

> The only way to make it make sense is add that we also know there is an entire spacefaring group of mercenaries whose entire hobby and/or job is deliberately throwing asteroids in Earths general direction.

Maybe there is, but they are hilariously incompetent?

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Re:Meltdown Proof-of-Concept by logfromblammo on Tuesday January 09, 2018 @05:56PM (#16110969)

Nah, they're really far away, and there's an accumulated round-off error in their distance conversion between bloits (used by the client) and metrons (used by the subcontractor), so they're shooting at a target a quarter of a light-year away, and won't realize it for another 500 years.

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Re:Meltdown Proof-of-Concept by Skunkleton on Tuesday January 09, 2018 @08:09PM (#16111748)

Bureaucracy to the rescue!

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Re:Meltdown Proof-of-Concept by abritinthebay on Tuesday January 09, 2018 @08:52PM (#16111982)

This sounds like a new BlackAdder pitch...

"Sir, I have a cunning plan" "Does it involve that legion of rabid space weasels again?" "... maybe."

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Re:Meltdown Proof-of-Concept by Skunkleton on Friday January 12, 2018 @07:59PM (#16137619)

As long as I can retire to my great big turnip in the country when it is all over I am happy.

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Re:Meltdown Proof-of-Concept by philsnow on Tuesday January 09, 2018 @12:45PM (#16108043)

you're being downvoted but the first non-trivial program `./kaslr` fetches the physical map offset of the running kernel: https://github.com/IAIK/meltdown/#demo-2-breaking-kaslr-kasl...

Note they do say

> This demo uses Meltdown to leak the (secret) randomization of the direct physical map. This demo requires root privileges to speed up the process. The paper describes a variant which does not require root privileges.

but I don't know how much allowing it to sudo speeds up the process.

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