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

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20
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5answers
4k views

Does too long a salt reduce the security of a stored password hash?

Suppose we have passwords that are statistically 7-8 characters long. Is appending a 200 character long salt less secure than a 5 character salt, because of the similar hash function inputs? I was ...
311
votes
4answers
97k 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 ...
1
vote
1answer
162 views

Best practices for usefully storing two factor authentication backup codes?

For a lot of web services offering two factor authentication, after setting up the system, you are given a short list of backup codes (one-time pads) that are around 7-10 characters long. These are ...
0
votes
0answers
59 views

Request for Google Password for Calendar Updates

A website that I trust (Delta Airlines) offers a link to add flight information to Google Calendar; that link opens a window asking for my Google login and password. Based on the advice in a similar ...
0
votes
1answer
128 views

Things to remember while building a password manager [closed]

I want to build a simple password manager for desktop whose sole purpose is to store the passwords that can be read by the user as and when required. I am not considering any fancy features such as ...
2
votes
1answer
242 views

Reverse Engineer this basic Hash using known answer?

Little background: I forgot one of my CCTV accounts password, so used the admin account to create a new one. However I can't access the old one as it's not possible to change a user account password, ...
0
votes
1answer
109 views

Please help clarify password hashing - salted, multiple iterations of MD5 vs bcrypt/sha2, etc [duplicate]

I was reading an article about the Ars Technica hack here and had a couple of questions. The commenter said: "PHPass uses salted and iterated MD5 to hash passwords" My question is that if I were ...
0
votes
1answer
141 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 ...
4
votes
1answer
327 views

entropy of FIPS-181 automated password generator

From wikipedia article on password strength: NIST recommends 80-bits for the most secure passwords Is there any estimation of entropy for FIPS-181 automated password generator? Recommended ...
4
votes
4answers
269 views

Using a password manager vs manual

was wondering, who still uses the traditional method of storing passwords (in envelope) in an actual physical safebox vs modern methods like password managers? what are the pros and cons of each ...
3
votes
3answers
1k views

sniff SSH password on the server

Is it possible on the server to log the password encoded by the remote user inside a log. I want to make a honeypot to see the type of user/password used.
1
vote
0answers
104 views

Rainbow Tables: Why do we need to store the last value of a chain?

Surely we could just make it so a rainbow table says for each beginning of chain do 10k iterations, and then we wouldn't have to store both values? Or does by doing it this way stop collisions?
1
vote
2answers
141 views

How to avoid referer information leakage during password reset

Most password reset systems involve emailing the user a one-time link that lets them reset their password. The token needs to be in the URL, as most email clients do not allow HTML emails to perform ...
15
votes
2answers
904 views

Distance between two passwords

It is known that people reuse their passwords across different sites. The reuse can be done in two ways: using exactly same password for two different sites, slight modifying the password of one ...
4
votes
2answers
280 views

Has a plaintext password ever been used in a court of law as evidence to a crime?

Regardless of how the password was obtained (decryption, bad hashing, confession): Are there any prior known cases where the contents of the password was used to prove motive or guilt? Or, looking ...
3
votes
1answer
748 views

what is a valid challenge for 2 factor authentication?

When designing password reset process: 1- Is a an email address or an assigned username a valid piece of information ( identifier) to ask for in two factor authentication? 2- How does two factor ...
1
vote
6answers
3k views

Pronounceable Password Generator

I am currently looking for a password generator which produces pronounceable passwords. I have used this random password generator a few years ago to generate a 42 characters long password and found ...
-1
votes
1answer
104 views

TLS/SSL and password transmission

I am still getting confused with security topics. At the moment the advantages and disadvantages of some of authentication methods are still not very clear. According to OWASP Authentication Cheat ...
48
votes
2answers
7k views

What should end-users do about Heartbleed?

What should one do about the Heartbleed OpenSSL exploit? mainly talks about what people running websites should do about Heartbleed. What should end-users of websites be doing? Do they need to ...
0
votes
3answers
113 views

Creating user and safely sending password

Assuming I currently use a safe way to salt-challenge-response-authentication-method, passwords are stored secured and all. I now question myself - how do users set the password? Meaning, they enter ...
50
votes
12answers
10k views

What to do about websites that store plain text passwords

I recently received an email from a popular graduate job web site (prospects.ac.uk) that I haven't used in a while suggesting I use a new feature. It contained both my username and password in plain ...
15
votes
1answer
801 views

Linux /etc/shadow password change security

I wonder what happens what happens when I am changing my password on a Linux system. Basically all passwords are stored in a file called /etc/shadow or /etc/master.passwd in BSD-like systems as I do ...
9
votes
3answers
4k views

Is LastPass' locally stored One-Time-Password recovery a security problem?

If you forget your LastPass master password then LastPass provides the possibility to recover access to your vault using a One-Time-Password (OTP) which is stored locally but is initially disabled. ...
1
vote
1answer
107 views

Domain socket authentication as in MySQL and PostgreSQL secure?

Are authentication mechanisms based on UNIX domain sockets (Linux) secure? And more specifically, are the respective MySQL and PostgreSQL implementations on Linux secure? The background for my ...
-1
votes
1answer
137 views

Why not use md5 auth mechanisms for IMAP over TLS?

I'm using Dovecot for IMAP connections. I've read a lot of tutorials on how to set up Dovecot, and a lot of them said to only allow: auth_mechanisms = plain login Why should I not allow *-md5 ...
4
votes
2answers
335 views

Including and storing the order of character entry in a password as an enhanced security measure

I'm sure I will be quickly corrected if this is a stupid idea, or if it has already been tried. My question is: has this idea been tried before? If not, are there good reasons it would not work, or ...
31
votes
8answers
5k views

Why must I have a “strong” password for sites like this? [duplicate]

I don't share any personal information with StackExchange, I'm not really worried about anyone trying to hack my account and I can't see any incentive for them to do so, and yet the password strength ...
4
votes
1answer
161 views

Soundness of GRC.com Haystack padding concept [duplicate]

I was wondering how sound is the concept presented by the Gibson Research Corporation (see below if you do not want to follow the link) about simple passwords (= very easy to remember) with the ...
0
votes
0answers
63 views

Detection of pass the hash

I have researched about PTH Attacks but yet found any solid way detecting it in a network.is there a way to detect a pass the hash ? analysing the windows message from the dcs or something ?
1
vote
1answer
284 views

What is the right way to implement Keyed Password Hashing?

As mentioned in this wonderful link, the way to get a PBKDF2 Hash of a user given password given a password (of course), a salt (generated Cryptographically Secure Random Number Generator. iteration ...
2
votes
2answers
115 views

Who can actually see the password when I accidentally used ftp instead of sftp?

It has been said that if we accidentally use ftp instead of sftp, people can actually see the login name and password in pure text form, and it is very bad. But who can actually see it? Will it be ...
4
votes
1answer
538 views

What is the best way to store password in memory (RAM) in Java?

Imagine there is a login form in Java application. We need assign usename and password to variables. Moment after we can Hash or HMAC password and keep it just for authentication step (no caching). ...
22
votes
4answers
3k views

How would you store a 4 digit pin code securely in the database?

I'm familiar with password hashing, using salts, bcrypt etc. But it doesn't seem like this would work to store a 4 digit pin code since the attacker could try all 10,000 combinations quite quickly. ...
5
votes
3answers
356 views

Are there any disadvantages to encrypting the password hash?

Is encrypting the password hash in database more secure than storing only the hash? Suppose we store encrypted SHA-256 result with AES instead of hash directly. Is this a good protection from a ...
3
votes
4answers
278 views

How effective are password checking websites? [duplicate]

I typed the following password in howsecureismypassword.net: yummy candy yummy It said it would take 100 billion years for a personal computer to crack. Is this accurate? Even though it has English ...
1
vote
2answers
142 views

Encrypted retrievable password

I have a password conundrum. I need to store an encrypted password in a DB table but in such a manner that would allow me to retrieve the password as plain text afterwards. Please note that this is a ...
23
votes
1answer
2k views

Facebook password lowercase and uppercase

Recently I logged into my Facebook account and then noticed that my caps lock was on. So I tried to log in again with and without capslock on. I got in both times. Then I tried to log in with the ...
15
votes
3answers
5k views

Is it possible to get the salt if I have the hash and original password?

Is it possible to get the salt if I have the hash and original password? My gut feeling is no, but would it be impossible or will it just take very long?
3
votes
1answer
1k views

Salt usage for Spring security?

I use the Spring security for Java web applications and I have written an authentication provider which is working without salt and now I want to either add salt or alternatively use the built-in ...
1
vote
1answer
101 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 ...
6
votes
3answers
282 views

Calculating password hashes in the browser?

I just finally got into Keybase and was surprised to see this in the sign-up page: Shouldn't password stretching and hashing be done on the serverside, as we normally don't trust a client?
1
vote
2answers
99 views

bscrypt,scrypt v/s iterative SHA-x [duplicate]

Both bcrypt and scrypt hashing algorithms are designed to increase the resources required during the computation. Hashing passwords with these algorithms can be beneficial as it makes the task of an ...
3
votes
1answer
69 views

Feeding PBKDF2 to SRP verifier creation

There is an older game that solely uses UDP to communicate, and I wanted to add password authentication to the game to facilitate things like experience points and rankings. To this end, I decided to ...
5
votes
1answer
133 views

What is preventing us to start using scrypt in production ?

After a lot of reading the expert opinion on password hashing, I understand that scrypt (which is both memory hard and CPU intensive) is a good candidate for password hashing. But I saw the experts ...
2
votes
1answer
168 views

Key's random art image is mostly black

I have generated an SSH key on Ubuntu 10.04 with ssh-keygen -t rsa -C "example@example.com" and the key's random art image comes out mostly empty (modified slightly): +--[ RSA 2048]----+ | ...
1
vote
1answer
159 views

How to suspend a silent oberserver from Facebook account?

A friend of mine told me about the following problem: She used to login on Facebook on a computer of her boyfriend. After they broke up she recognized that he was able to login to her account from his ...
1
vote
0answers
143 views

Password automatically typed into user box on facebook [closed]

Just want to ask some questions regarding on this strange experience while logging on my account on Facebook There are cases that I'm accidentally typing my password into the username box of the ...
0
votes
1answer
145 views

How many passwords should I have? [closed]

So I am upgrading my personal security. Most passwords that I use are generated by and stored in a password manager. There are a few places where I cannot use a password manager -- here, I plan to ...
139
votes
8answers
19k views

Why are salted hashes more secure?

I know there are many discussions on salted hashes, and I understand that the purpose is to make it impossible to build a rainbow table of all possible hashes (generally up to 7 characters). My ...
1
vote
1answer
138 views

Finding Plaintext Password Repositories [closed]

I came across a file, that was used by our tech support, to store all generic usernames and passwords in them for use with new systems. (Our company has been trained on the use of other Password ...