3
votes
1answer
61 views

Is there an actual use for OpenPGP authentication keys?

The OpenPGP specification (RFC 4880) describes, page 34, the different capabilities that an OpenPGP key may have; including: 0x20 - This key may be used for authentication. In GnuPG, one of the ...
1
vote
2answers
92 views

How can I analyze password recovery tokens?

All websites that support authenticated user interactions have a password recovery feature. Usually they will email the password reset link through which you can easily recover your account by typing ...
1
vote
1answer
46 views

MySQL authentication, how to pad the 20-byte salt

Im authenticating with a mysql server with the authentication method listed here. I observed the salt and hash using wireshark, and I know the password, but I am having trouble reproducing the hash I ...
2
votes
2answers
77 views

How do clients enroll using SRP?

From what I understand, one of the benefits or Secure Remote Password (SRP) is that is does not require reliance on certificate authorities. In a scenario where clients need the ability to register as ...
8
votes
3answers
502 views

Location to store an encryption key

I'm building a secure system which stores messages on a server in a Postgresql database. The messages are stored encrypted with PHP's openssl_encrypt() function with the AES-256-CBC method. At the ...
3
votes
3answers
117 views

How to make authenticity of text verifiable without third party services?

There is a person who wants to establish a system which allows her/him to publish texts anywhere and make it verifiable that s/he is the true origin of that text. Only the first message is not ...
2
votes
0answers
1k views

How are “security levels” of identities in TeamSpeak 3 implemented?

TeamSpeak 3 VoIP communication system uses a concept of so called identities to identify the client to the server. These identities are basically public/private key pairs. In order to prevent people ...
2
votes
3answers
192 views

Can a zero knowledge proof of voting be made using a trusted auth server (without client side crypto)?

Questions: Can one implement a secure voting system having all the features described below? e.g. without disclosing any individual's vote to the government server (or the third party), preserving ...
1
vote
0answers
47 views

Putty Event Log

Can anyone explain me the Step by step process of Key Exchange that takes place while accessing Linux machine using Putty ? I found the Event Log of Putty but the Various Key Exchange didn't make very ...
2
votes
4answers
458 views

Does using WPA2-Enterprise just change the attack model vs WPA2-PSK?

As far as I can tell based on the reading I've done so far, WPA2-Enterprise uses the same encryption and security algorithms and methods as WPA2-PSK, with the addition of using another service for ...
1
vote
0answers
47 views

Any Suggestion Exchanging shared key between process via port in untrusted machine (infected my malware)?

I am trying to get shared key between Firefox extension and a java program running in same machine. I am communicating both application via socket. My assumption is that malware is running in ...
0
votes
2answers
94 views

SSL/TLS Question [closed]

I am currently working on my SSL/TLS assignment and I got a question to ask. What is the use of a login password since it is not needed for establishing secret communication between your computer and ...
0
votes
1answer
66 views

Payload authentication + HW-SW Binding

I want to authenticate a (2nd stage) bootloader during the boot process using a symmetric key, which is derived from HW properties of the platform the bootloader is running on. Thus, I want to bind ...
3
votes
2answers
249 views

Totally secure public key distrubition

Public-key cryptography secures communications provided that you use pre-shared public-keys. The problem is how to share these public-keys while maintaining authenticity? How can we be sure that ...
3
votes
2answers
95 views

System for securely authenticating content acquisition

I'm having trouble designing a system for authenticated content from my site distributed by other people. I'm working in Ruby on Rails, but I don't think that at a theoretical level my question isn't ...
0
votes
2answers
281 views

Algorithm to generate NTLMv2 Hash in PHP

I am trying to develop a PHP function to calculate NTLMv2 hash by providing server & client challenge, domain, account and password. The resulting hash appears to be not correct. Can someone ...
0
votes
2answers
344 views

Is there a way to configure WPA2-PSK to provide Forward Secrecy?

Is there a way to secure an wireless connection against a decryption attack where the PSK is known (E.G. Airdecap-NG)? Is it possible to configure Forward Secrecy on 802.11 Wireless Connections?
0
votes
1answer
262 views

What are the performance and security tradeoffs when selecting “ECC” or “Subgroup” in a U-Prove token?

In one of the U-Prove documents, I remember reading something that compared Subgroups versus ECC and it went something like this (paraphrased): Subgroups Requires a bigger key to achieve equivalent ...
2
votes
0answers
56 views

What flexibility does a “Third party gamma” offer to U-Prove deployment?

The U-Prove SDK has the following comment: (link) // 1: CA-RA split (a party trusted by the issuer provides the gamma value) Given that the Gamma value (if provided) overrides the Attributes value, ...
2
votes
0answers
58 views

In U-Prove, what is the purpose of “Pseudonyms”, “Committed”, and “Scope” values and how are they used?

U-Prove allows for anonymous authentication and authorization without the involvement of an IdP. When a client generates a presentation proof 3 values can be optionally included, but I can't find ...
8
votes
1answer
320 views

Build a secure channel without SSL/TLS

I'm looking at possible options to build a secure channel between multiple embedded devices with limited cryptography capabilities and an HTTP server (It could be some sort of web service). 1. ...
12
votes
3answers
882 views

Multi-tenancy, SSL Certificates, and Subject Alternative Name

The X509 specification allows a CA to issue a single certificate for multiple hostnames, by using the "Subject Alternative Name" extension. From the spec: The subject alternative name ...
5
votes
2answers
232 views

Do keyfiles actually add any meaningful security in the presence of strong passwords?

In the context of protecting access to local encrypted files or devices against a determined (and competent) adversary, is there any reason to believe that the use of a key file actually presents a ...
9
votes
2answers
462 views

Is it okay to sign a PGP key without an IRL meeting?

[PGP] can get paralyzed by excessive analness. — Phil Zimmermann Preamble I am in the process of building my own web of trust. That is, I want people (PGP users…) to be—fairly—sure that, by ...
5
votes
1answer
149 views

Security and authentication problem

We have a sample scenario and we would like to receive some feedback and some solutions regarding possible security schemes. First of all, lets imagine a real world scenario: Imagine that a user ...
1
vote
2answers
289 views

How high is the entropy of this salt-generating code? (No code-reading actually necessary)

What is the best method? Assumption: I have a function that generates a number of medium-high entropy bytes Step1: I generate 3 of these medium-high entropy bytes. Step2: I hash these bytes using a ...
2
votes
2answers
146 views

Easy protocol for email authentication

I'm cooking up a very simple system to send commands to a remote server via email. Everytime an email is sent to do_something@mydomain.net, the server runs a python script that does something ...
2
votes
4answers
983 views

SSH: reusing public keys and known-man-in-the-middle

Usually, people recommend to use a single private-public key pair everywhere (if we're not talking about a possibility of compromising the private key): Best Practice: “One per-user ssh key” or ...
1
vote
2answers
304 views

Can I use hardware token OTP to stop piracy?

Our firm sells an offline desktop (.exe) software, we are thinking of using OTP (from hardware token like in internet banking) to stop people from copying the software without permission. Basically, ...
1
vote
1answer
288 views

Storing Private Keys Generated on Server with specific User's Password Securely

I am currently building a system (PHP Web Application Framework) that creates an RSA Key Pair for a user to allow other users to send secure information from one to another. The public key is ...
4
votes
1answer
324 views

Can I re-use another vendor's dual factor token in my own system? (Avoid physical token bloat)

I read the open source multifactor authentication techniques called HOTP RFC 4226 and TOTP RFC 6238 and realized that a single random number is the basis for the token's cryptography... and that this ...
1
vote
1answer
410 views

How does the YubiKey Validation Server work from an encryption perspective?

Many YubiKey servers rely on the free cloud hosted authentication that comes with the product, but I'm interested in keeping all cryptographic material in my control. For that reason I am looking at ...
1
vote
1answer
111 views

Reasonable computationally lightweight security?

I've read a bunch about how one should use bcrypt or PBKDF2 as a good middle ground between tunable workload and acceptable time to make brute force and collision attacks unfeasible. What if the ...
4
votes
2answers
2k views

When using symmetric key encryption, do we need to sign?

Say we're using a shared key between two parties, that has been distributed using public key encryption, is it still necessary to sign any data that's encrypted using the shared key? Or is it enough ...
1
vote
0answers
171 views

Verifying Authenticode signed executables and DLLs using OpenSSL API [closed]

I have installed openssl and now the rsa_test.c is running fine. What I want to do is: Open any exe or dll digital certificate. Extract the Thumbprint and PublicKey. The public key contains the ...
8
votes
5answers
621 views

How do RSA fingerprints protect from MITM attacks?

I understand that RSA fingerprints are used to verify that you are really connecting directly to who you want to connect to, and not someone else posing as that site. Like when you do a git push, it ...
-1
votes
2answers
123 views

Should I use salt to authenticate data?

I have a client and a server. The client makes a request containing userId, cardId, position (on the card) A hacker could just do the same http request with the next position. So I think about ...
7
votes
4answers
3k views

HTTP Basic auth password storage more secure than Digest auth

If you are using SSL already, it appears Basic auth is the way to go since you can perform bcrypt with the password when you store it in the database, where as Digest auth only allows md5. As we know, ...
15
votes
4answers
373 views

Why aren't digital signatures the standard way to authenticate web clients?

The web is a mess of incompatible cookie schemes, asinine requirements ("your password must contain letters, numbers, and at least one symbol from !()-_., and must begin with a letter, and once you ...
2
votes
3answers
520 views

Establish a secure channel with mutual authentication given pre-shared public keys

Suppose I have a system whereby parties are identified by their public key (with some pre-selected asymmetric key algorithm). Suppose I have a party PUB1 which wants to establish a secure channel with ...
1
vote
2answers
109 views

How do i use a guessable ID for authentication

This question doesn't fit well in many categories but hopefully someone's run into it before. I'm developing a web api that will interact with a physical device. Each new physical device has it's ...
-1
votes
1answer
170 views

About important hacks in history [closed]

I would like to know how important hacks happened, because I can figure out how they hacked a website but I can't figure out how did they hacked into NASA International Space Station source code. Or ...
8
votes
2answers
756 views

HMAC Based Request Signing - Storing the Salt

I'm working on a (non high security) project that currently isn't live but might go live at some point. We have a REST API (implemented using Restlet and Neo4j) running on a server and an Android ...
4
votes
2answers
984 views

MAC vs Encryption

I understand the difference between MAC (eg. hmac_sha256, etc.) and Symmetrical Encryption (eg. rc4, etc.), but my question is what advantage does MAC solve that using encryption doesn't? I know that ...
3
votes
4answers
689 views

Can we prevent a man-in-the-middle attack with symmetric-key cryptography?

Suppose that Alice signs the message M = "I love security" and then encrypts it with Bob's public key before sending it to Bob. As well known, Bob can decrypt this to obtain the signed message and ...
6
votes
4answers
3k views

HMAC/PBKDF2 vs Simple hashing algorithm for web service authentication?

We are in the process of creating a web service and have been investigating ways of securing it. In reality, the service is likely to get very little traffic and the data is likely to be of little use ...
4
votes
1answer
753 views

How secure is TOTP key on phones?

Our company is considering several options in moving to MFA with software OATH TOTP or yubikey OATH OTP. In regards to where the secret is stored, I'm aware that a yubikey or similar hardware device ...
7
votes
1answer
1k views

How will security need to be changed if P=NP?

If we suppose that it is found that P=NP, how will security measures need to be changed? I'd like to know the major security measures that are affected, and how they would need to be changed. We can ...
7
votes
6answers
1k views

Prevent denial of service attacks against slow hashing functions?

I've been thinking about bcrypt recently, and what I wonder is if there's a way to deal with the inherent (D)DoS problems with slow hashing functions. Namely, if I set up bcrypt so my machine takes ...
2
votes
2answers
252 views

Does secure remote password verifier transmission need to happen out of band?

With relation to the necessity of a verifier being transmitted from the client to the server prior to any handshake steps, I was wondering how this is supposed to happen securely? To me this seems ...