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RAMBleed Attack – Reading Bits in Memory Without Accessing Them

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121–130 of 141 posts

Re: RAMBleed Attack – Reading Bits in Memory Without Accessing Them

#121

Earlier quoted context omitted.

>unlike Rowhammer, RAMBleed does not require persistent bit flips, and is thus effective against ECC memory commonly used by server computers. Seems like mitigations for Rowhammer is not enough for RAMBleed.

ECC isn't effective mitigation against Rowhammer either. https://www.vusec.net/projects/eccploit/ tl;dr ECC logic can't cope with 'single' errors involving > 2 bits.

It has to cause a huge amount of single-bit errors to find a spot suitable for a three-bit error.

If these errors are actually treated as errors, then chips will be disabled or processes will get blacklisted long before they can be used to exploit.

So this is really "ECC is often configured wrong", not "ECC isn't effective".

Re: RAMBleed Attack – Reading Bits in Memory Without Accessing Them

#122

Earlier quoted context omitted.

> SAL annotations Are there tools for developers to use these (e.g. with VC++), or are they all Microsoft internal?

Yup there are a few static code analysis tools that support using annotations afaik

SAL specifically, or other kinds?

Re: RAMBleed Attack – Reading Bits in Memory Without Accessing Them

#123
post #110

Earlier quoted context omitted.

Real-world side channels are going to start getting more attention as the technology and techniques for extracting information from EM radiation from circuits (not radios) leaking state improve.

I was unaware that there were high-speed digital circuits that weren't also radios.

Just ones that people have particularly strong feelings about being radios

Re: RAMBleed Attack – Reading Bits in Memory Without Accessing Them

#124
post #103

Earlier quoted context omitted.

Well "special hardware to detect EM radiation" is most often software-defined radios like HackRF or BladeRF among others down to TV reception dongles you can get for a few dollars (search for RTL-SDR)

I look forward to the day when SDRs are inside smartphones.

They probably already are just hidden behind closed source firmware

Re: RAMBleed Attack – Reading Bits in Memory Without Accessing Them

#126
post #113

Earlier quoted context omitted.

There is also this: https://docs.microsoft.com/en-us/visualstudio/code-quality/u...

I think they talk about the annotation but not the analysis tools?

https://docs.microsoft.com/en-us/visualstudio/code-quality/c...

It's part of VC++.

But I do not recommend using SAL for modern code.

Re: RAMBleed Attack – Reading Bits in Memory Without Accessing Them

#127
post #116

Can we talk about these attack names? Everything bleeds these days. "RAMSack" is a legit missed opportunity.

“Bleed” has a functional purpose; it communicates that it is a side-channel leaking information.

"Bleed" is normally just used for communicating that the exploit leaks data. See Optionsbleed, Heartbleed and Ticketbleed which are not side-channel attacks afaik.

Re: RAMBleed Attack – Reading Bits in Memory Without Accessing Them

#128
post #126

Earlier quoted context omitted.

I think they talk about the annotation but not the analysis tools?

https://docs.microsoft.com/en-us/visualstudio/code-quality/c... It's part of VC++. But I do not recommend using SAL for modern code.

Oh wow. I'd used /analyze before but I hadn't realized it takes SAL into account. I thought it just does limited extra analysis without SAL. Thank you!

Re: RAMBleed Attack – Reading Bits in Memory Without Accessing Them

#129

Shortly after I joined Microsoft in 2004, all new feature work on Windows Longhorn (Vista) was halted. There had been yet another high profile computer virus on Windows XP caused by a buffer overflow. It was an all-hands-on-deck type moment. Everyone spent weeks adding SAL (source-code annotation language) annotations to the entire Windows code base. SAL annotations enabled automated source code analysis to identify…

Firmware and microcode updates.

Re: RAMBleed Attack – Reading Bits in Memory Without Accessing Them

#130

Shortly after I joined Microsoft in 2004, all new feature work on Windows Longhorn (Vista) was halted. There had been yet another high profile computer virus on Windows XP caused by a buffer overflow. It was an all-hands-on-deck type moment. Everyone spent weeks adding SAL (source-code annotation language) annotations to the entire Windows code base. SAL annotations enabled automated source code analysis to identify…

Dependent types can prevent buffer overflow attacks without any additional runtime overhead.
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