Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [side-channel]

A side channel attack is an attack that deduces secret information from environmental observations such as timing or power consumption.

9
votes
2answers
655 views

What are the new MDS attacks, and how can they be mitigated?

Several new hardware side-channels were discovered called MDS attacks, which allow reading arbitrary memory, like Meltdown. Many existing mitigations are useless against them. The relevant CVEs are: ...
0
votes
0answers
73 views

How to defeat confirmation-of-a-file attack? [duplicate]

Suppose you want to upload some files to an online storage without the storage provider figuring out what you have uploaded. The obvious thing to do is of course to encrypt the files. However, we ...
12
votes
5answers
3k views

Are variable time comparisons always a security risk in cryptography code?

I came across the cryptography python package, and noticed it had the following about reporting security vulnerabilities: Examples of things we wouldn’t consider security issues: Using a variable ...
0
votes
2answers
52 views

Is is possible to get the TLS implemetation information of the remote server?

I am trying to devise a way to find side-channels that reveal exact TLS library (and its version) running on the remote server by adopting similar approach to JavaScript Template Attacks However, if ...
2
votes
2answers
211 views

What CPUs does the Spoiler attack affect?

I see on different websites different information about the Spoiler Attack. Some websites say all Intel CPUs are vulnerable and other websites say only Intel Core CPUs are vulnerable. Are Intel Xeon ...
2
votes
2answers
79 views

Could always-listening mobile apps secretly spy on conversations?

Various apps and services available on modern smartphones constantly listen with the mic (e.g. Siri or Google Assistant listening for wake word, "Now Playing" feature on Pixel phones). To settle user ...
0
votes
1answer
151 views

badBIOS reflashing

This is not a has-badBIOS-pwn3d-me post, so don't worry about any paranoid rants. Having read a thorough analysis/debunking of the alleged evilware, I certainly understand that the technology badBIOS ...
3
votes
1answer
68 views

To what extent are countermeasures against side-channel attacks effective/ used regularly by everyone?

I'm doing an Extended Essay for IB right now and I'm doing it on how secure RSA is. As side-channel attacks are one category of attack, I was wondering (as I am struggling with the conclusion) while ...
0
votes
1answer
51 views

Do any speculative executation attacks affect ARMv7 CPUs?

Do we know if there are speculative execution attacks that affect ARMv7 CPUs at this time? Are there any theoretical risks that need further investigation?
4
votes
1answer
467 views

Can speculative execution on intel cpu be disabled?

In the light of all the recent Intel Vulnerabilities with speculative execution, can speculative execution be fully disabled to protect from all this vulnerabilities, from BIOS or OS kernel? Maybe ...
2
votes
3answers
153 views

Is malware on an air gapped computer a requirement to communicate over side-channels?

Is it a requirement to infect the air-gapped pc with malware at first to get all needed functions for a communication path between air gapped pc and attacker pc? For example: Stuxnet, first was the ...
4
votes
1answer
240 views

If rowhammer only results in capacitor discharge, how can it flip 0 to 1?

In rowhammer, why will changing the voltage on one row cause the other row to open/close? Is it related to induction? How can it change bits from 0 to 1? I understand from 1 to 0 - voltage discharge, ...
1
vote
0answers
40 views

How does cache partitioning prevent covert/side-channel attacks? [closed]

In a report on an open-source separation kernel (Muen kernel) I was reading, in the future work section, it says that cache coloring can be implemented to prevent covert/side-channel attacks. It is ...
5
votes
3answers
2k views

Is the Linux kernel vulnerable to LazyFP (CVE-2018-3665)?

Recently, a side-channel attack was discovered that exploits lazy FPU state switching to leak the contents of MMX, SSE, and AVX registers. The vulnerability can only be exploited when lazy FPU saves ...
1
vote
1answer
76 views

Does Speculative Store Bypass Attack Require Assembly/Source Code Knowledge?

ok, so the gist of speculative store bypass attack to my understanding is that, cpu chooses the most frequent code path, bypass the if/else test and just assumes that it's true/false and then execute ...
1
vote
1answer
160 views

Does OpenSSH use padding of random lengths?

According to the end of RFC 4253 § 6, the random padding introduced to each SSH packet is an arbitrary multiple of 8. It mentions that random padding lengths can mitigate traffic analysis: Note ...
3
votes
2answers
307 views

Change the function such that there are no more side-channels

Given is the function compareKey which is a part of a crackme (a binary file). Which side-channel attack can be used to find the right password (password is made up by ASCII coded big and small ...
1
vote
0answers
49 views

Can cache attacks be executed on a single thread architecture?

Despite an extensive research on the subject, I'm wondering if there exists side channel attacks based on cache use which are conducted on single threaded architecture, smart cards for instance. I'm ...
1
vote
0answers
650 views

Side channel attack with flush+reload

I have been reading about cache side channel attacks and the "Flush+Reload" method came up a decent amount. Before putting forth my question, this is what I understand about the Flush+reload technique....
2
votes
1answer
82 views

Are there techniques or methods to develop security protocols without side channel attacks?

In general timing attacks are a manifestation of the implementation. So if I am processing data on the server or the client then I can leak information depending on how the code is written. To ...
11
votes
1answer
570 views

Why does this cache attack work?

I was recently reading the following paper about doing a cache attack in Javascript: https://arxiv.org/pdf/1502.07373v2.pdf But I was confused by how it could work. In the paper, an 8 MB buffer was ...
1
vote
1answer
199 views

how do CPU cache side-channel attack fit into the background of Meltdown vulnerability? [duplicate]

NOTE:I know there are similar questions out there, namely this one, but that answer is just an extraction from original paper, which didn't clarify the attack. Additionally I can see from answers ...
2
votes
2answers
239 views

How does the side channel actually access the contents of kernel memory in Meltdown?

In the Meltdown paper it mentions it can identify kernel memory address being accessed. The part I don't understand is how the FLUSH+RELOAD channel works to identify what the contents of the memory ...
4
votes
2answers
234 views

Will patching a higher layer protect against the spectre/meltdown vulnerability in a lower layer?

The question I am about to ask is similar to the following question: Do I need to patch Linux for Meltdown/Spectre if the hypervisor has been patched, and I trust the guest? However, I would like to ...
167
votes
3answers
15k views

Meltdown and Spectre Attacks

Canonical question regarding the 2018 Jan. disclosed Meltdown and Spectre Attacks. Other identical or significantly similar questions should be closed as a duplicate of this one. Main concerns What ...
5
votes
1answer
343 views

Can Spectre be fixed in future hardware simply by purging CPU caches?

As far as I understand it, Spectre is caused by speculative execution not completely undoing all side effects of an incorrect branch prediction (specifically, not undoing a CPU cache write). Doesn't ...
2
votes
2answers
510 views

Is it secure to type in sensitive data in bash / shell scripts

So lets say I have a .sh script and I have to input a password in it , will there be some kind of cache where the bash inputs are stored ? And if yes please tell me whre so I can ersase it . Would the ...
5
votes
1answer
93 views

Get key by monitoring power consimption of AES hardware core?

Is it possible for an adversary to gain knowledge of the secret key by analyzing the power consumption of an AES hardware core? I think he/she can't, but I am having difficulty to give a reasonable ...
1
vote
1answer
274 views

What are mitigation techniques against Cache-timing attacks on AES?

I read here a paper of Daniel Bernstein This paper demonstrate complete AES key recovery from known-plaintext timing of a network server of another computer. This attack should be blamed on the AES ...
4
votes
1answer
302 views

Side channel attack on SSD?

I know it is possible to obtain the key from some cryptographic schemes by using side channel attack on hard drive such as noise and magnetic fields. I was wondering if it was possible to use side ...
2
votes
1answer
232 views

side channel attack vs eavesdropping attack

I wonder if there is a difference between side channel attack and eavesdropping attack. To me both seems similar
1
vote
1answer
400 views

Evaluation board for side channel attacks [closed]

I have started working on side channel attacks particularly focusing on DPA and DEMA for different cryptographic algorithms; targeting FPGA devices. I want to measure the power and EM radiated out of ...
7
votes
4answers
432 views

Simple defense against power analysis?

I would like to hear your opinions and how effective would my proposed defense is against power analysis. It is one of the nastiest side channel attacks because it's undetectable and passive, but ...
1
vote
0answers
176 views

How to prevent cache-based side-channel attacks in IoT devices

The sharing of hardware resources from various vendors in the Internet of things is fundamental for efficient processing in the cloud. The presence of a myraid of clients accessing the same hardware ...
19
votes
2answers
2k views

Principles of cache attacks

There are many scientific publications that deal with cache attacks. Most recently, the CacheBleed attack was published which exploits cache bank conflicts on the Intel Sandy Bridge architecture. Most ...
7
votes
1answer
66 views

Is flushing of all caches on any context switch between mutually-distrusting processes the only way to prevent cache timing attacks?

This article demonstrates a devastating Javascript-based cache timing attack that allows for cross-VM tracking of mouse movements and other activities by web pages. Is the only way to prevent cache-...
19
votes
4answers
3k views

Detect non HTTP packets using port 80

We are currently doing port whitelisting on our firewalls which is working well but this of course does not prevent the implementation of side channels or the misuse of these ports for other purposes. ...
3
votes
1answer
6k views

Covert, Overt, and side channels

I am really confused between the following three terms: Overt Channel. Covert Channel. Side-Channel. I feel frustrated! I've been searching about them to find a clear explanation but I keep getting ...
1
vote
1answer
2k views

Timing side-channel attack example

I understand that timing side-channel attack is a measurement of time taken to execute cryptographic algorithms. I'd like to see a simple example that explains how timing attack takes a place on any ...
0
votes
1answer
94 views

Questions about Side Channel Signal/Attack

I have a few questions about side channel signal/attack that could save my life. I need experts who have enough knowledge or has done this experiment to answer this questions. 1) What type of ...
1
vote
1answer
31 views

Usefulness of Server's Work Load given Timing Attack Resistance of Responses

I've read articles in the past discussing the importance of having timing attack resistant responses for information where knowing the time for evaluation would leak information about the data being ...
37
votes
8answers
6k views

Should I worry about remote timing attacks on string comparison? [duplicate]

Say we have a Java web application which uses a shared secret to verify the identity of the client. The secret is stored on the server, and the client transmits the secret over SSL where it is checked:...
-2
votes
3answers
430 views

How to mitigate side-channel attacks?

Say I am at my office. I am now trying to talk to my friend with a LUI instant message application. I have a blanket covered over my keyboard, just like Snowden, probably good enough to hide my ...
2
votes
0answers
210 views

OpenPGP smartcards compromised by blackhat 2015 simcard hack?

This blackhat was a new sidechannel attack in the SIM-card AES encryption announced. I am currently using the OpenPGP smart/SIM-card version 2.1 to store my PGP-private keys, which is the same model ...
2
votes
0answers
518 views

How to do side channel attack on smart cards? [closed]

Assume that I have a smart card and I want to do a differential power side channel attack on its mutual authentication mechanism. This is the mutual authentication mechanism that my card using(Let ...
4
votes
3answers
591 views

Software defense against cold-boot attacks

Cold boot attacks are particularly nasty. On Android, a solution is to use a Nexus device with a locked bootloader to preven flashing a custom recovery. On a PC, your safeguards are even more limited....
9
votes
5answers
976 views

Origin of side-channel attacks

What is the origin of side-channel attacks? Is it related to the algorithm or to the implementation? In other words, is the software responsible for the attack or the hardware? Is there a ...
1
vote
3answers
1k views

Constant time compares when array sizes are not equal?

What is the preferred or recommended way to pursue contestant time compares when array lengths are not equal? Should we exit as early as possible? Something like: if (array1.size() != array2.size()) ...
2
votes
1answer
182 views

Are servers that do not implement time services vulnerable to clock skew attacks?

An article describes clock skew attack possibilities §§: These can be attacked by repeatedly connecting to the hidden service, causing its CPU load, hence temperature, to increase and so ...
14
votes
5answers
3k views

Can sites which check your password as you type pose a security risk?

Some sites that I use check my password as I type it into the login (not registration) form. So, for example, to begin with I might have: Username: sapi ✓ Password: passw × and by the time I've ...