269

This is an active area of research. I happen to have done some work in this area, so I'll share what I can about the basic idea (this work was with industry partners and I can't share the secret details :) ). The tl;dr is that it's often possible to identify an encrypted traffic stream as carrying video, and it's often possible to estimate its resolution - ...


259

Yes encrypt, it is easy. Plus according to a 2014 Software Engineering Institute study 1 in 4 hacks was from someone inside the company with an average damage 50% higher than an external threat actor. Link to source: https://insights.sei.cmu.edu/insider-threat/2017/01/2016-us-state-of-cybercrime-highlights.html Although this is the 2017 version.


223

Yes, it is possible. However, that runs the risk of destroying the device without getting the data off first, which is undesirable. It also does not achieve the political goals of forcing Apple to assist in decrypting the device, paving the way with precedent for the flurry of future requests of this sort to come, some of which are certain to have less ...


212

Because the cards contain a chip which are powered by a coil. The coil is not really a antenna, but half of a transformer. Think your regular mobile charger. This contains a transformer, that will transform the voltage from 230V or 120V AC to 5V DC. This is done by having a coil magnetize some iron, and this iron magnetizes the "receiving coil". If you draw ...


205

According to Google, the difference is with handling referrer information when clicking on an ad. After a note from AviD and with the help of Xander we conducted some tests and here are the results 1. Clicking on an ad: https://google.com : Google will take you to an HTTP redirection page where they'd append your search query to the referrer information. ...


192

No, this is not a good practice. There are two distinct problems. encrypting the password instead of hashing it is a bad idea and is borderline storing plain text passwords. The whole idea of slow hash functions is to thwart the exfiltration of the user database. Typically, an attacker that already has access to the database can be expected to also have ...


186

Hibernate the computer If the ransomware is encrypting the files, the key it is using for encryption is somewhere in memory. It would be preferable to get a memory dump, but you are unlikely to have the appropriate hardware for that readily available. Dumping just the right process should also work, but finding out which one may not be trivial (eg. the ...


170

It's not just about you. By forcing users to use TLS, they're creating a more secure environment for everyone. Without TLS being strictly enforced, users are susceptible to attacks such as sslstrip. Essentially, making unencrypted connections an option leads to the possibility of attackers forcing users into unencrypted connections. But that's not all. ...


168

Right now the question is a bit broader: RSA vs. DSA vs. ECDSA vs. Ed25519. So: A presentation at BlackHat 2013 suggests that significant advances have been made in solving the problems on complexity of which the strength of DSA and some other algorithms is founded, so they can be mathematically broken very soon. Moreover, the attack may be possible (but ...


161

You can distribute the key now and send the message later. Suppose you are a spy sent on a mission behind enemy lines. You take the key with you (secure distribution) and when you discover a secret you can securely send it using the One-Time pad.


160

Why do people buy red sport cars ? They do not go faster than sport cars of any other colour... AES comes with three standard key sizes (128, 192 and 256 bits). Many people see this and think that if there are three distinct sizes instead of just one, then there must be some difference, and since the 256-bit version is a bit slower than the 128-bit version (...


156

You should never send passwords in the clear, nor should you store them in the clear. You should hash them using a slow one-way cryptographic hash such as bcrypt or PBKDF2. If a user forgets their password, you offer them a "reset password" function, which sends a one-time reset link to their account. A scheme such as the following is reasonable: Hash all ...


155

I recommend the Secure Secure Shell article, which suggests: ssh-keygen -t ed25519 -a 100 Ed25519 is an EdDSA scheme with very small (fixed size) keys, introduced in OpenSSH 6.5 (2014-01-30). These have complexity akin to RSA at 4096 bits thanks to elliptic curve cryptography (ECC). The -a 100 option specifies 100 rounds of key derivations, making your key'...


151

As usual, journalism talking about technical subjects tends to be fuzzy about details... Assuming that a true Quantum Computer can be built, then: RSA, and other algorithms which rely on the hardness of integer factorization (e.g. Rabin), are toast. Shor's algorithm factors big integers very efficiently. DSA, Diffie-Hellman ElGamal, and other algorithms ...


142

Chrome not only stores your password text, it will show it to you. Under settings -> advanced -> manage passwords you can find all your passwords for all your sites. Click show on any of them and it will appear in the clear. Hashed passwords work for the site authenticating you. They are not an option for password managers. Many will encrypt the data ...


137

Of course you can start small and implement your own algorithms. But do not assume they provide any security beyond obfuscation. The difficult thing when it comes to cryptography is finding reasons why something actually is secure. You won't be able to decide that within months and if you feel like you are at that point, you are most probably wrong. It is ...


135

There's several possibilities. They could be storing the full password in plaintext, and only displaying the last 4 characters to the support person. They could be hashing the password twice. Once hashing the full password, and again with just the last 4. Then the support person types in the last 4 to see if it matches the hashed value. The problem with ...


130

Now THAT is a good question. We must first give a precision: many one-way functions, in particular hash function as commonly used in cryptography, accept inputs from a space which is much larger than the space of output values. For instance, SHA-256 is defined for inputs which are strings of up to 18446744073709551615 bits; there are 218446744073709551616-1 ...


119

It's not uncommon, but it may not be required. A lot of developers seem to forget that HTTPS traffic is already encrypted - just look at the number of questions about implementing client side encryption on this website - or feel that it can't be trusted due to well-publicised issues such as the Lenovo SSL MitM mess. However, most people weren't affected by ...


116

We can analyze your setup by comparing it against a system known to be not tamper proof, the Sony PlayStation 3. OS control You have no control over the OS. Sony did write the OS themselves. Size of the OS The PS3 OS can be very simple as it just needs to boot games. Windows is a generic OS, with many, many functions. This exposes many API's. Shell The ...


113

You can't. To securely send information over an unsecure channel, you need encryption. Symmetric encryption is out, because you would first need to transport the key, which you can't do securely over an unsecure channel[*]. That leaves you with public key cryptography. You could of course roll your own, but you don't want to be a Dave, so that's out, ...


112

The answer always depends on your threat model. Security is always woven into a balance between security and usability. Your approach inconveniences the hackers trying to break into the account, but also inconveniences a user who merely mistypes their password. If the fake account is believable enough to fool an attacker, it may also be believable enough ...


110

What are the real world chances that someone would steal his identity? Running a MITM attack on an HTTP connection when on the same LAN is basically trivial. ARP is not designed to be secure. Some high end switches provide reasonable mitigation, but it is mostly pretty weak on anything that is not fabulously expensive. There is an employee complaining ...


109

You can't, plain and simple. If you don't trust the hosting company, you don't host with them. This is law #3 from 10 immutable law of security: Law #3: If a bad guy has unrestricted physical access to your computer, it's not your computer anymore. The hypervisor always have privileged position over your virtualised machine, you can't protect yourself ...


108

In SSH, two algorithms are used: a key exchange algorithm (Diffie-Hellman or the elliptic-curve variant called ECDH) and a signature algorithm. The key exchange yields the secret key which will be used to encrypt data for that session. The signature is so that the client can make sure that it talks to the right server (another signature, computed by the ...


107

Option 1 is more secure. In option 2, we can guess each word seperately. When we guess "amazing", we get confirmation that this word is correct and we can continue to the second word. In option 1, we have to guess all four words at the same time. You may think that one GPG offers some security, and four GPGs offer four times that security, but it doesn't ...


105

The point is to protect against your disk being accessed outside of the OS. Encryption is useful against attackers who have physical access to your computer. Without it, it would be trivial to read out the content of your home directory, for example by plugging in a live boot USB stick.


104

In a word: sufficient. This is block-level encryption, so it is filesystem-independent. Ubuntu's transparent encryption is done through dm-crypt using LUKS as the key setup. The built-in default for cryptsetup versions before 1.6.0 is aes-cbc-essiv:sha256 with 256-bit keys. The default for 1.6.0 and after (released 14-Jan-2013) is aes-xts-plain64:sha256 ...


103

The NSA is a composite organization, that comprises several sub-entities called "directorates" with various scopes and goals. The NSA, as a whole, is supposed to have a multitude of roles; its signal intelligence role (often abbreviated as SIGINT, i.e. spying) is the one most people talk about, and is supposed to be handled by the SID (as "Signal ...


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