Specific to the security of passwords: hashing, entropy, cracking, resets, lockouts, etc.

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2answers
123 views

Forced to use using 2-Step Authentication to keep online profiles safe?

I am starting to see a majority of services, websites, and social networks offering the 2-step Authentication like crazy now to protect their users. Also, after reading how the Twitter Account N was ...
1
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1answer
2k views

Why is it considered safe for services like Mint to store bank password?

My understanding is that, typically websites are recommended to store only hashes of passwords using one-way cryptographic hash function. This way, there is no way to retrieve the passwords even when ...
6
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6answers
17k views

Recommend Length for Wi-FI PSK?

I currently have a network set up with WPA2 and AES encryption, the password is 8 characters long but was randomly generated and contains no dictionary words. However I'm concerned about the ...
2
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1answer
127 views

Should a space in a password count as a symbol when checking for complexity?

There is no doubt in my mind that spaces should be allowed in passwords. I see some websites disallow spaces, symbols in passwords and even enforce minimum length which seems t otally nonsensical to ...
1
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1answer
58 views

Storing encryption passphrases in memory in Dalvik?

Given KeePassDroid, I'm considering some of the security implications of accessing KeePass databases on an Android device. In the native applications for Windows, OSX, and Linux, whenever the ...
1
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3answers
363 views

RatticDB for passwords is not encrypted. Is this good approach?

I am looking for a password application for storing passwords, and RatticDB have a web interface and SSH access is planned, which are exactly the features I am looking for. However, they write that ...
0
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0answers
43 views

Is there a FIPS 181 like standard for random password generation with alphanumerical seed?

NIST recommends FIPS 181 as a random password generator for "easy to remember" passwords. As far as I understand the standard: it will generate a password that is lowercase, and with some ...
3
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4answers
252 views

Ethical brute force demo on a web login when knowing the password complexity requirements

We are currently having accounts compromised at a substantially high rate. Some in the organization believe that our password complexity requirements is enough to thwart brute force attacks. I wanted ...
3
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1answer
77 views

SAML, and forcing a re-authentication

I have a use case forced upon me by industry regulation. I wish it wasn't there, but it is. A user logs in to my service, navigates around, etc. The user can perform many actions, but one of the ...
38
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2answers
5k views

Is it good practice to ban an IP address if too many login attempts are made from it?

Since an IP address does not necessarily represent a specific device, but probably a whole network/company/etc. does it at all make sense to block an IP address if there is a significant amount of ...
1
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1answer
108 views

Is there anyway to generate a SAM file?

I was wondering if it is possible to create a windows SAM file. I already tried using chntpw but it seems like it only works under a Redhat based linux, ie I was able to blank/change a Windows 7 ...
2
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2answers
180 views

Locality Sensitive Hash (LSH) function to approximately match old passwords

Recently, I ran across a website that requires me to change my password after X number of days had passed since I had last created one. Intelligently, the service made sure that the password did not ...
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1answer
140 views

Exploiting Writeable SNMP

So, I've come across a couple of devices that are using default writable community names for SNMP such as 'private' (on windows machines) and 'Secret c0de' (on Brocade switches). I'm aware of the ...
1
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3answers
127 views

Touch tone phone username and password

I just got off the phone with Fidelity, who manage the health benefits for the company where I work. Before talking to a person, I was prompted to enter my username and password on the numeric keypad: ...
15
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2answers
542 views

Can client-side hashing reduce the denial-of-service risk with slow hashes?

When storing user's passwords that you need to verify against (but not use as plaintext) the current state of the art is: Hash the password Use a salt Use a slow hash function - bcrypt, scrypt, etc. ...
14
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2answers
1k views

How many passwords does the average user know?

Looking for research on the count and complexity of passwords that an average user is actively using. Note: Also, just to be clear, by research, this is not a request for you to respond with an ...
268
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4answers
78k views

Do any security experts recommend bcrypt for password storage?

On the surface bcrypt, an 11 year old security algorithm designed for hashing passwords by Niels Provos and David Mazieres, which is based on the initialization function used in the NIST approved ...
4
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3answers
212 views

Why use Keepass, etc. if all your passwords are in one place?

I'm a firm proponent of using a password manager like Keepass to generate and store secure passwords. I also encourage others to do the same. But there's always one person who says they'll never use ...
18
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2answers
11k views

Why are GPUs so good at cracking passwords?

What is it about GPUs that lets them crack passwords so quickly? It seems like the driving force behind adopting good key-derivation functions for passwords (bcrpyt, PBKDF2, scrypt) instead of ...
4
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11answers
4k views

Definitely safest password storage scheme?

I already asked this on StackOverflow but I was suggested this would be a better suited place and I found no way to "move" the question so I have to copy it. Believe, I know, there are hundreds ...
10
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7answers
5k views

Forgotten password or reset link, which is more secure to email?

I originally posted this as a reply here in this thread but didn't get much feedback on it, and now I'm curious as to what others think is the best approach, or if there is any difference between the ...
21
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6answers
6k views

Is AES encrypting a password with itself more secure than SHA1?

This isn't really a practical question, but more a question of curiosity. I heard a CS professor recommend stepping up from md5ing passwords not to SHA1, but to AES encrypting the password using ...
6
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4answers
1k views

Security of the KWallet password encrypting application?

According to http://gaganpreet.in/blog/2013/07/24/kwallet-security-analysis/ , the KWallet password management system is quite weak, it uses key splitting, Blowfish 56, and no salt. The key ...
0
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1answer
160 views

How compromised should I assume my computer is?

I had turned ssh on a while ago to do some remote work, and didn't turn it off (yes, I'm an idiot). I was just looking over some netstat info when I noticed someone had established an ssh session with ...
273
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12answers
46k views

How to securely hash passwords?

If I hash passwords before storing them in my database, is that sufficient to prevent them being recovered by anyone? I should point out that this relates only to retrieval directly from the ...
0
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2answers
100 views

How secure would this method be considered for password storage

Ok I am currently storing the passwords in most secure way I could think of. With use of Encryption and Hash. The passwords are first generated by user as plain-text with minimum length of 6 ...
1
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1answer
175 views

Any reason I shouldn't be salting and hashing before putting through bCrypt?

I've been reading up on password storage and such, and have come to the conclusion that I need to be using bCrypt. I've got an implementation working correctly, but I'm wondering the best way to move ...
0
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3answers
525 views

Authenticating users to Web Apps without sending password — can anyone suggest improvements?

I have been interested in implementing authentication method for a web app that is run in modern browsers, without having to send the password over the wire. Can anyone suggest improvements or even ...
170
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7answers
37k views

Why would you not permit Q or Z in passwords?

Jetblue's password requirements specify that, among other stringent requirements: Cannot contain a Q or Z I can't fathom a logical reason for this, unless it were say, extremely common for the ...
0
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1answer
870 views

Why do websites limit password length? [duplicate]

I just made a new account with some eGov service (Belgian government). I use LastPass (which generates long, random strings for each site), But the system told me that the maximum allowed length was ...
1
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3answers
106 views

Is it possible to have a high confidence that a password is not being reused?

Have a few thoughts on the topic, but the general gist is if a user inputs a new password, is it possible to have a high confidence that a password is not being reused elsewhere? By elsewhere, I mean ...
7
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4answers
196 views

What standards are there for mangaging high value passwords?

I am leading a small team at a start-up and I am facing a dilemma with high value passwords. I am the only one on the team who knows all the key passwords for production servers, databases ... etc. ...
2
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2answers
186 views

Dual Authorization (Social Auth 2.0)

Can you see any obvious challenges to requiring 2+ users to confirm authentication requests using an association such as a friendship type of relationship. A practical application would be an ...
0
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2answers
82 views

Precise measurement of password complexity

I am thinking on a system, which measures the complexity of a password not based on its entropy or compressibility, but with a simply sophisticated method. The measurement of the ...
3
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3answers
193 views

How can a site know about insecure password?

I received an email from my web host recently that informed me I had an "insecure" password on one of my email accounts and that I had to change it. Their definition of what a secure password is as ...
1
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1answer
109 views

Challenge-response login without storing a password equivalent

A problem with many challenge-response login systems is that the server has to store a password equivalent. For example, if the server stores SHA1(salt + password), and an attacker captures that hash, ...
18
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4answers
4k views

Security of passphrase-protected private key

If an attacker obtains a private key that was created with no passphrase, he obviously gains access to everything protected with that key. How secure are private keys set up with a passphrase? If an ...
1
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2answers
96 views

What impact do the frequency of password resets have on password reuse?

Wondering if there's any research behind the most common password reset cycle I've seen of 90-days, and if there's any research that gives any insight into how to optimize password resets to reduce ...
2
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1answer
476 views

Hydra bruteforce and JSON

I am having problems with Hydra and a JSON payload. The login request (intercepted with Fiddler), is the following: POST http://architectureservice.test.com/api/v1/login HTTP/1.1 Host: ...
3
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4answers
467 views

Best practice for forgot password form, ok to leak that a given e-mail is invalid

On our forgot password reset form, is it ok to leak that a given e-mail address entered is invalid? Or should we always just return success and check your e-mail, even if the e-mail is not valid. I ...
3
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0answers
402 views

A Google owned IP address accessed my outlook account [closed]

Today I got a warning from Microsoft saying that there was unusual activity on my account. Diving deeper I saw that there was a successful sign in from a Google owned IP address (according to ARIN). ...
55
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8answers
89k views

Where can I find good dictionaries for dictionary attacks?

I’m wondering where I can find good collections of dictionaries which can be used for dictionary attacks? I've found some through Google, but I’m interested in hearing about where you get your ...
0
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2answers
305 views

Securing passwords for REST Authentication

first post on sec so go easy. I'm developing a REST application using the Spring Framework, as as part of the requirements, we have to secure the different functions of the system to different user ...
3
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1answer
101 views

How does “Google password monitoring” work?

Google Apps has a feature to monitor users' password strength and notify administrator about it. Google help says: View the length of each user's password along with a graph showing its relative ...
3
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2answers
1k views

Is it a good idea to store Email addresses as hash only?

I am currently building a web service at http://write-math.com similar to http://detexify.kirelabs.org/ that should help users to get LaTeX code from drawn formulae. It is part of my bachelors thesis ...
61
votes
3answers
16k views

How does Google Authenticator work?

Google Authenticator is an alternative to SMS for 2Step verification, installing an app on Android where the codes will be sent. It works without any connectivity; it even works on plane mode. This ...
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3answers
69 views

Is it ok to use the same password for many services with two-factor authentication?

Let's say that I've a relatively strong password, but I don't want to use many different passwords for each different service, and let's say that those services provide two-factor authentication using ...
8
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3answers
1k views

Logging “password with counter” use

When prompted to update their passwords after they've become stale (whether that's after 30, 60, 90 days — whatever is implemented by policy), many users simply increment the number that they may have ...
55
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7answers
36k views

Certificate based authentication vs Username and Password authentication

What are the advantages and drawbacks of the certificate based authentication over username and password authentication? I know some, but I would appreciate a structured and detailed answer. UPDATE ...
42
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3answers
8k views

Paypal sent an email addressing me with one of my old passwords as my name

I got this email from service@intl.paypal.com, with the title: Your account has been limited until we hear from you. I think this is a scam / spoof email because I don't see any notification in my ...