Resources to learn more about Side-channel attacks?
cryptanalysis - How practical are side-channel attacks and how much of a concern are they? - Cryptography Stack Exchange
How practical are side channel attacks?
"Well known crimes" or vulns using side-channel attacks
Videos
For those who don't know here is a neat description of it from the wikipedia:
"In computer security, a side-channel attack is any attack based on information gained from the implementation of a computer system, rather than weaknesses in the implemented algorithm itself (e.g. cryptanalysis and software bugs). Timing information, power consumption, electromagnetic leaks or even sound can provide an extra source of information, which can be exploited."
It looks like a very fascinating branch of studies. I mean break and explore vulnerabilities from radio, electromagnetic leaks, audio, and other things are super groovy.
Also, I am particularly curious about it because I plan to include this as one of the major plot points in a book that I am planing inspired by Gibson, Stephenson, Watts, and Egan. Resumidely my idea is to write about a hacker group operating in the middle of the decade of 2030 composed of transhumanists, occultists, biohackers, and more other unique people. Who decide to migrate from AI-powered spear-phishing and identity theft to other forms of attacks like side-channel vectors. So I am looking to resources to learn more about this type of attack to satisfy my intellectual curiosity, thanks in advance.
Yes, side-channel attacks are practical and a real concern, if the past is indicative of the future.
I've been professionally involved with Smart Cards since the mid eighties, and have repeatedly witnessed deployed systems vulnerable to many forms of side-channel attacks; examples (I personally did 1 and 3):
- RAM buffer not cleared at reset, readable (with standard command Get Response), leaking state of previous PIN comparison, even if incrementing the PIN presentation counter had been inhibited (by hardware reset or/and removing EPROM programming voltage); that allowed recovering the 4-digit pins with expected 5000 attempts.
- Timing dependency where the duration of PIN presentation with permanent-memory writes inhibited leaks if the PIN is correct or not, to the same effect.
- Timing dependency where the duration of a comparison between values leaks the index of the first incorrect byte, allowing finding an $n$-byte value with expected $n\cdot2^7$ attempts instead of $2^{8\cdot n-1}$.
- Return to manufacturer test mode (by a software exploit, hardware modification or upset), allowing extraction of permanent memory content, including secrets (variant: normal software can be coerced to read the wrong location).
- Micro-probing to spy on bus lanes, leaking all kind of secret information.
- Simple Power Analysis directly leaking bits of exponent in RSA.
- Simple Power Analysis leaking activity (e.g. start programming of permanent memory), which combined with timing measurement leaks sensitive information (e.g. good or bad PIN, before that is recorded).
- Differential Power Analysis, allowing key recovery.
- Fault Injections (often considered side-channel attacks).
I have seen this causing great embarrassment to the suppliers of the vulnerable Smart Cards, and believe multiple reports that in the (distant) past, such vulnerabilities occasionally have been exploited on a large scale, especially in the field of Pay-TV with Smart Card.
More generally, when a device using cryptography is broken, this is often by means better described as a side channel attack than a cryptographic attack.
Addition: check this introductory article's part1 (alt.), part2 (alt.), part3; and this 2012 paper showing remote SPA and DPA attacks on Smart Phones and PDA.
If a cryptographic device/system can get in the hands of the adversary or otherwise become accessible enough (timing/Tempest/DEMA/SPA/DPA attacks can be remote to some degree), and it contains any information which confidentiality or even integrity matters (such as secret/private keys, authenticators, counters..), then one needs to pay close attention to side-channel attacks.
So, when building a system which uses cryptography (be it public or symmetric key), how practical of a concern are such attacks?
Any class of attacks becomes a practical concern the moment it starts to become attractive for an attacker with respect to other classes, and provided any successful attack brings rewards that outbalance the cost. That is true also for side-channel attacks; if your system can be compromised much more easily by other simpler means (e.g. social engineering, software bugs, test modes, you name it), spending money or time on adding protection against side-channel attacks may not make much sense. Same thing if the attack takes 1 year to mount and all you get is the ability to post on someone's Facebook wall.
And, what guidelines can be followed to determine if your systems needs protections (be they power analysis protections, emissions, timing, etc)?
A risk analysis is the first tool to guide you in identifying which attacks vectors are relevant (e.g. which system properties leak information to an attacker). For instance, if you trust the physical environment and its surrounding and your system is connected to external networks, you can ignore electromagnetic radiations, but not timing, padding oracle attacks, cache attacks and so on.
After that, you can implement some countermeasures where possible.
I’m not familiar with side channel attacks. To measure the power or timing, it seems you need physical or remote access to the hardware simultaneously with the user. But at that point, you probably have access to the data in that machine (unless due to permissions).
How prevalent are side channel attacks? Are they mostly of academic interest?
Hello,
I am looking for "well known" public examples of side channel vulnerabilities. Maybe in common products or data breaches or similar things. Of course I would also be interested in general cases aswell if they are compelling to non technical people in the field. Basically I am holding a presentation on side channels for a diverse audience and I would like to motivate the talk by giving common everyday or impactful examples, rather than just talking about directly about the one side channel I researched with its techncial breakdown straight away.
I would be especially interested if you know of any cases where side-channels were used in some capacity in comiting a crime (smart card cloning for example). That would enable me to talk about happened events with a date and a little story behind it which would hopefully make the technical part of my talk more engaging.
Thankyou for helping me out here if you happen to know any good examples