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Reading privileged memory with a side-channel

googleprojectzero.blogspot.com

461–470 of 639 posts

Re: Reading privileged memory with a side-channel

#461
post #133

What are the odds that the NSA already knew about this? Roughly 100%?

Pretty close to 100%.

Google zero and academia researchers found it independently, following some talk about the concept a while back.

The 3 letters agencies have people of the same calibre working full time on that. They could find it too.

Re: Reading privileged memory with a side-channel

#463
post #142

Earlier quoted context omitted.

Why would you do that? If you are concerned for the security of your coins, you should have moved them to a wallet you own that is not hosted on an exchange. The bank you transfer your dollars to is just as likely to get hit by the exact same vurnerability. In addition you have to pay a fee to move your coins, then to wire the dollars to your bank account. Moving from crypto to fiat is also liable to taxation. If the…

The majority of coins on Coinbase are in cold-storage and crypto on Coinbase is insured against this type of breach. I personally wouldn't panic to get my coins out.

There was an announcement not long ago saying they are not insured.

Re: Reading privileged memory with a side-channel

#464

It seems that Richard Stallman is not so paranoid after all: > I am careful in how I use the Internet. > I generally do not connect to web sites from my own machine, aside from a few sites I have some special relationship with. I usually fetch web pages from other sites by sending mail to a program (see https://git.savannah.gnu.org/git/womb/hacks.git ) that fetches them, much like wget, and then mails them back to me…

RMS remains a rambling nutjob and none of this is really applicable to the issue at hand.

A "rambling nutjob" that has been proven correct time and time and time again.

We need more people with RMS-type views in Google, Facebook, etc.

Re: Reading privileged memory with a side-channel

#465
post #115

Papers describing each attack: https://meltdownattack.com/meltdown.pdf https://spectreattack.com/spectre.pdf From the spectre paper: >As a proof-of-concept, JavaScript code was written that, when run in the Google Chrome browser, allows JavaScript to read private memory from the process in which it runs (cf. Listing 2). Scary stuff.

This is so incredibly bad. Spectre is basically unpatchable . We can do better than we are now with patches but it's all just turd polishing, essentially. A proper fix will require new CPU hardware. And as a kicker? Leaks are basically undetectable.

New CPU microcode is enough, though at a performance price. On pre-Zen AMD there is also a chicken bit to disable indirect branch prediction. (It feels good to be finally able to speak about this freely!!!)

I don't know for which processors Intel and AMD plan to release microcode updates.

Re: Reading privileged memory with a side-channel

#466
post #375

Can someone more knowledgeable than me in regards to this vulnerability tell me: 1. How to best protect my local personal data from being subject to this? 2. Whether I should seriously consider pulling all my cryptocurrency off of any exchanges?

from my understanding:

1:

- install security updates for your OS - if it's not ready yet: disable JavaScript in your browser by default and enable it only for resources you trust. otherwise just skip the page. execute third party code with extra caution. any suspicious code should go away (even not inside vm)

2: as long as it's stored in a wallet on your own hardware which you fully control, it should be safe enough

Re: Reading privileged memory with a side-channel

#467
post #127

The papers take a while to get to the point. I nearly fell asleep re-reading the same statements until they got to the point: speculative execution of buffer overflows. Could have been said more concisely. Sadly, this seems to be the norm with academic texts.

It gives all the required context, much needed for an "average" engineer to understand it. Without that, most of the people, except the microchip engineers, would have to read about the related topics first anyways. I personally was surprised at how understandably everything was explained.

Re: Reading privileged memory with a side-channel

#468
post #284

Earlier quoted context omitted.

You are wrong. Install the NoScript extension and you can see your site without js. NoScript also allows you to selectively enable js per site on a temporary or permanent basis. This is the default way that I and many other people browse the web. https://noscript.net/

Just looking around, general available figures for public internet (as opposed to tor) suggest that anywhere between 0.1% to 1.0% of users have JS disabled. These numbers have also been consistently going down over time. That's a fairly small number to dictate how a system should be designed.

Right. It’s like designing for any other tiny group: color blind, blind, people who don’t read any of the 3 languages your site is already translated to, etc.

I’m not saying that shouldn’t be done, but business wise its probably usually best to instead add design changes for the latest smartphone screen.

The web isn’t a hypertext graph anymore, it’s a large JavaScript program with a thin html front now.

Re: Reading privileged memory with a side-channel

#470
post #348

Azure's response: https://azure.microsoft.com/en-us/blog/securing-azure-custom... This part is interesting considering the performance concerns: "The majority of Azure customers should not see a noticeable performance impact with this update. We’ve worked to optimize the CPU and disk I/O path and are not seeing noticeable performance impact after the fix has been applied. A small set of customers may experience some…

Interesting that they left it this late.

Disclosure: I work on Google Cloud.

Like the AWS reboots, people will notice. So in the interest of the embargo, both Azure and AWS waited to update as late as they felt was safe. Since we do live migrations and host kernel updates all the time, nobody noticed us :).

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