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5

You should always use an AEAD mode if you can, especially over the network. Crypto++ seems to support GCM, which is a good AEAD mode that has seen use in TLS 1.2. (There are others that are just as good, but TLS's "star power" lends GCM a lot of credibility.) Importantly, AEAD modes authenticate "additional data." This is unencrypted data not included with ...


5

So both of your scenarios rely on the attacker having root access to the phone. In security, it's generally considered that once an attacker has root access, it's game over. That said, there are still interesting things to be said about your question. You asked: Is there a situation where the secure element does offer a clear security benefit to this ...


4

One system I've seen is to use dynamic license codes. Each time the software is run, it connects back to the vendor's server. It submits the current license code, and is issued a new one. The old license code is invalidated. If the VM is cloned, then only one clone will have the new license code. Drawbacks with this system: Internet access is required to ...


4

Your question as originally posted is not very clear. If you require Public Key / Asymmetric Encryption algorithm, the safe/simple choice is to use RSA with a 2048 or better key size. If you require a plain Symmetric encryption algorithm, a good choice is AES-256. The keys should be created from a Cryptographically Secure random number generator. For ...


4

I was wondering whether a CA has different private keys to sign certificates with? In general, no. There is one key pair - and thus private key - per certificate. Certificates can be rolled over to use a new key pair of course. Furthermore, in general, a CA manages multiple certificates for different purposes. The CA may also have different certificates ...


3

Passwords are concerned with system access. They are used to verify that you are who you say you are (example: logging into email), or at least that you are someone that is allowed to access the resource you are trying to access (example: a code to open a door). The important thing about passwords is that they are fed into a system, so extra measures like ...


3

I was wondering whether a CA has different private keys to sign certificates with? A CA will usually have a number of Intermediate Keys for use in signing customers' certificates. These Intermediate Keys are in turn signed by the CA's Root Key, which should be stored "offline" and only used rarely to sign those Intermediate Keys. The matching Root ...


3

Many countries publish Security standards for cipher suited. In US, you can rely on pci dss standard, fips 140-2, ANSI, EAL, etc. In France we have the RGS which indicate the algorithms and key length which can be trusted and how many time we can rely on. I guess every industrialized country has the same standard. I personally choose to follow this ...


3

Most vendors using SSL/TLS commonly use OpenSSL who keeps a detailed record of vulnerabilities associated with SSL/TLS. Subscribing to security sites like Bugtraq will keep you in the loop regarding disclosed (known) vulnerabilities associated with OpenSSL and may tell you about the other SSL libraries as well. You would also want to subscribe to other ...


3

Hushmail does something like this (or used to). The private key was stored locally and the website would send a Java applet to handle encryption/decryption and signing operations. It would protect you against the vector you describe... but... the whole model of a web application handling PGP has serious limitations. When you log on to the compromised ...


3

In cryptography you don't have just one opponent who attacks you in the way you expect him to. This is what makes it hard to reason about, because you have to think of absolutely EVERYTHING. But really, nobody can possibly outsmart every possible opponent. The best we can do is utilize our common knowledge and existing research as much as possible and take ...


3

How do software companies ensure that their product or app can only run in a given number of bare-metal or VM instances? They don't! Software companies start with some half-a**ed technologies that are incomplete solutions. These are then watered down so they don't break the user model too badly. In the end, the only thing that software licensing does is ...


2

Actually most implementations of algorithms like BCrypt will generate a salt on their own, from the random source of the operating system. This is the best one can do and there is no need to derrive a salt from other parameters. A salt should be globally unique for each password, so an attacker cannot find any precalculated rainbow-tables, and would have to ...


2

Yes, why not. Key generation (including key generation for ECDH) and private key operations are relatively efficient compared to other cryptosystems such as RSA. There are some things to keep in mind: standard ECC operations such as ECDSA do require a good random number generator to be present; the small key size makes it relatively simple to use quantum ...


2

If you want information about the estimated strength of the ciphers, I still recommend the 2013 ENISA report. I don't know of any constantly updated list, but the only way the assumptions in that report can change is if some cipher is broken (in the cryptographic sense, not necessary relevant in practice), and that will be widely reported, if it is made ...


2

One of the biggest issues that you face is not the algorithms you choose, but how you implement using them. There are many good algorithms for various purposes, and virtually any of them, improperly applied, can result in a disastrously broken cryptosystem. This is one of the reasons people offer advice like "use libsodium" because libraries like ...


2

Most ransomware use strong encryption algorithms, which means that you will have a hard time trying to decrypt the encrypted files without the corresponding decryption key. The malware uses an AES key to encrypt files. The AES key for decryption is written in the files encrypted by the malware. However, this key is encrypted with an RSA public key embedded ...


2

1.) See openssl output below and excellent Wikipedia page below 2.) No not all of them, see the tables at the URL below. 3.) No not all of them, see the tables at the URL below. https://en.wikipedia.org/wiki/Transport_Layer_Security openssl ciphers -v 'ALL:!aNULL' ECDHE-RSA-AES256-GCM-SHA384 TLSv1.2 Kx=ECDH Au=RSA Enc=AESGCM(256) Mac=AEAD ...


2

What you need to do is encrypt the file(s) before uploading it to the cloud provider, and decrypt them on download. Assumptions You do not want to cloud provider to by able to read (decrypt) these files. You would like something simple to implement Do This Use a symmetric algorithm to encrypt the files. The most common secure algorthm is AES There ...


1

As an addon to Trey's answer: I use the string ALL:COMPLEMENTOFALL when want I every cipher suite. I use the -V (upper case V) option to make OpenSSL output the hex-IDs of the cipher suites. Note: OpenSSL is not authoritative for answering these questions. IANA is. (But I couldn't get their CSV file parsed nicely.) $ ./openssl version OpenSSL 1.1.0-...


1

I am not sure I can answer this question perfectly, but I'll try. First off, think of symmetric algorithms. One such algorithm is a method to encipher(encrypt) a message, and must be completed with a key, in order to tell the algorithm exactly how to encipher said message. The enciphered message is called cipher-text. The recipient of the cipher-text must ...


1

I have contacted the authors and they were very helpful. The original quote says it all: The book is about randomized algorithms that act on data sets. You can always view these as deterministic algorithms, which take two inputs -- the data set, and also a string of random bits. The definition of differential privacy has a probability operator, and ...


1

McNerdHair is correct to require you to use an authenticated mode. There are more options than GCM mode though: GCM mode is fast. It is sometimes called a 1.5 pass authenticated mode because of the fast GMAC calculation. It is standardized by NIST. CCM mode is another NIST certified mode specifically created for packet encryption, i.e. transport mode ...


1

My question is are they talking about whole javax.crypto package ? No. They are referring to the Crypto provider for javax.crypto. Do I need to remove these all ? No. So long as you did not manually specify to use the Crypto provider, you are fine. Search your code for the string "Crypto" (with a capital C).


1

To answer the question you specifically asked...No, hashing the Int32 value to use as the salt is not significantly stronger than using the Int32 directly. It would, as you already suspect, be more obscurity than security. As Martin pointed out in his answer, the key property of a salt is that it be globally unique. You do not get this property with ...



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