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

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3
votes
3answers
131 views

Is it a good idea to use non-Latin Unicode characters in a password?

I've heard many suggestions as to what makes a good password (hard to guess, not a dictionary word or permutation thereof, at least a certain length, etc.) so that it cannot be cracked in a realistic ...
27
votes
4answers
3k views

Is it safe to store a password hash history for preventing user to keep same password repeatedly in some cases?

I am developing an application in PHP and it uses bcrypt encryption to store passwords. I want to keep the history of hashes whenever the user changes the password. By doing this I want to stop the ...
-1
votes
2answers
157 views

SHA256 to text or MD5

I want to decrypt a sha256 to text. Is there a way other than bruteforcing to decrypt sha256? Like if I convert that SHA256 to MD5 and then try decrypting?I know its hard and the possible way for ...
2
votes
0answers
51 views

Disallowing Similar Passwords [duplicate]

Upfront, I want to clarify that I am not a professional cryptographer, I am more curious about playing with the math and science behind it, and also want to improve my habits with my own personal and ...
1
vote
5answers
617 views

Authenticate user without knowing their password

I'm working on a project where each each user will have a public/private RSA key-pair. Users will be able to send encrypted messages to each other using the each target user's public key so that only ...
1
vote
0answers
41 views

Hashcat Turkish character problem [closed]

I'm using cudahashcat, it haven't special chars like "öçşĞÜ" in standart charsets. I defined charsets with windows-1254 and other encoding types(and -1 öÖçÇğĞşŞüÜıİ?a parameter), i tried but they ...
1
vote
2answers
197 views

Is SpiderOak truly “zero-knowledge”?

I've recently changed SpiderOak password on computer A. Because I have SpiderOak installed on computer B as well, I thought I will have to update the password on it so the application can connect to ...
2
votes
1answer
70 views

Do I have an SSH password?

I have an Ubuntu server hosted on DigitalOcean, I have been using SSH keys since the very beginning. (You can chose for it to be setup before the server instance has even been created). So I have ...
5
votes
2answers
239 views

ProtonMail security concerns

This TED talk brought me here. First of all, to those who created ProtonMail: Nice job!!. Regardless of what people say, it's definitely a big step forward from tradition options like Hotmail, Gmail ...
2
votes
1answer
168 views

Trusted Platform Module (TPM) secure password

I'm trying to set secure Trusted Platform Module (TPM) passwords on a network and would like to set it to the maximum length possible. How long can the TPM's password be? Is it limited by bits or by ...
-4
votes
1answer
43 views

What is the most secure way to protect a custom CMS from infiltration? [closed]

I have a custom CMS with a randomly generated ASCII 100-character string from this site for both my username/password. I also have this following sha512 encryption system, which was created by ...
2
votes
1answer
51 views

Is it safe to signup multiple applications with facebook?

Putting all eggs in one basket.. Is it safe to sign-up on different applications with facebook or such similar platforms, linkedin, twitter etc?
1
vote
2answers
53 views

Password strength in Wordpress Network

Very similar to this question at Wordpress Development, but intentionally asked here. A password, that contains: at least one capital letter, at least one small letter, at least one number and at ...
0
votes
2answers
126 views

Is my hashing function good enough

Is there an obvious flaw with this hashing function (written in PHP)? function hash($password) { sleep(1); // Make hashing slow $hash = ""; $iterations = strlen($password); for ( $i = 0; $i ...
1
vote
1answer
230 views

How are “worst passwords” lists made?

I don't understand how it's possible to create a list of the worst passwords used if they're (allegedly) encrypted? Are they collected anonymously before saving in the database especially for this ...
6
votes
3answers
67k views

Wordlists on Kali Linux?

I notice that in /usr/share/wordlists in Kali Linux (former Backtrack) there are some lists. Are they used to bruteforce something? Is there specific list for specific kind of attacks?
0
votes
2answers
87 views

Need some docs that say we shouldn't upper the string when saving it as a password [closed]

I'm trying to find on the Internet some manual, guide or policy secure about applications should not convert lower string to upper string to store as password I mean, don't make ...
2
votes
1answer
73 views

What is a key-hardened hash?

I've seen the term 'key hardened hash' used to describe a recommended way to tighten up password hashing. What does this mean? Can it just mean to use a pepper?
17
votes
6answers
2k views

What does “random” mean in the context of password creation?

Disclaimer: as you will see from my question I'm a total outsider in this subject, just very curious. I was wondering how easy it would be to crack a password-protected RAR5 file, and I found many ...
3
votes
3answers
149 views

Acceptably secure solution for users to log in with a short unique code only (no username)

I am creating a website whereby users are given an account by invitation only, and are sent a unique code by post. Users can then log in (at least the first time) by entering the code only. The goal ...
34
votes
11answers
26k views

Are password-protected ZIP files secure?

Following my answer. If I can list contents of password-protected ZIP file, check the file types of each stored file and even replace it with another one, without actually knowing the password, then ...
-2
votes
1answer
241 views

What are common problems that reveal PHP code? [closed]

What is the best method for securing PHP scripts that contain database passwords? From what I've read, PHP can be revealed when an error occurs and is not caught. Is there any way to reveal PHP by ...
0
votes
1answer
129 views

What kind of backdoor can be made after hacking wi-fi? [closed]

I'm interested to know if A hacks B's wifi password, what can A do to gain persistent access to the router even after B changes the wifi password? Secondly, how can we detect the backdoor and patch ...
20
votes
4answers
2k views

Recommended policy on password complexity

Is there any research on how how a password complexity policy can increase or decrease the quality of passwords? If you don't have any requirements on the password then probably 90% of users will use ...
7
votes
3answers
1k views

SSH key auth, but still need password for sudo?

SSH with public-private key authentication comes enabled by default with most Linux distributions. This is great because when I create accounts for remote users I don't have to email them sensitive ...
4
votes
2answers
346 views

LastPass login security

If LastPass does not store your master password, then how can you login to use their web app? Surely you must type it in, it is sent over using SSL, and then salted/hashed on the server-side, and ...
5
votes
3answers
1k views

Is GPG suitable as part of a password manager and generator?

I assume that GPG is very strong to crack, guess, etc. Since I have confidence in GPG, would it be appropriate to use my GPG key as the master key for a password manager or generator?
1
vote
3answers
138 views

How to transform an hash into a usable password?

I was reading about PwdHash and it inspired me to create a little project where you input a master password and an easy to remember alias into a password hash, like bcrypt, and then you get an hash. ...
7
votes
4answers
439 views

Decentralised password recovery

Are there good/established techniques for password/key recovery in situations without a centralised service? (Anything goes, but I'd prefer solutions that distribute the recovery information across ...
1
vote
1answer
64 views

Password sharing with spouse or mate (bulk-change shared passwords (via cloud service))? [closed]

I've read on New Scientist magazine that in 80% of all cases when people in a relationship share a place where they live one of the spouses knows the other's password, thus making the question I am ...
1
vote
2answers
217 views

Longer passwords vs Password Composition Rule [duplicate]

Password composition rule is being considered as a burden for the users and some experts are recommending the increase in the password length instead of enforcing users to comply with the composition ...
1
vote
3answers
127 views

Trouble understand login vulnerabilities

I'm testing my own web page with the following vulnerabilities. #1: Form escapes ' to \' So if a user tries to enter the following information: username: 'or'1=1 password: m username will ...
0
votes
1answer
42 views

Framework behind password reset mechanism

I have always seen those "Forgot password" links from web sites that requires some form of user login. Can I get a deeper understanding of how this works? What tools/framework do I need to use because ...
1
vote
1answer
660 views

Hydra sometimes fails against my own router known password

Hydra sometimes fails against my own router known password. Sometimes confirms it was found, and sometimes returns unusual error code (empty). What does this means? dione@saturno:~/misc$ hydra -l ...
1
vote
1answer
83 views

What is the safest way to encrypt a password that can be decrypted at a later time?

In a web app I'm building, I need to use Apple's AutoIngestion tool for iTunes Connect. In this tool it seems the only way to use it is to send a password in plain text. What would be the best ...
4
votes
3answers
372 views

SSH Public Key Authentication vs Username/password for API Access

I have a linux device that will be making periodic call to an API server, say everytime the system boots up. Everytime then it should authenticate itself and then do its thing. I can either store the ...
50
votes
9answers
8k views

Generic error message for wrong password or username - is this really helpful?

It is really common (and I would say it is some kind of security basic) to not show on the login page if the username or the password was wrong when a user tries to log in. One should show a generic ...
2
votes
0answers
28 views

sample/starter code to test for TRUSTe password requirements [closed]

Considering its a requirement for Truste certification I figure that the code to test for a password meeting Truste's password strength requirements has been written more than a few times. I was ...
2
votes
2answers
63 views

Does changing the default number of iterations in KeePass (or other encryption applications) increase security?

Inspired by this question about the difficulty of cracking a KeePass database, I'm wondering if changing the default number of iterations in an encryption application (e.g., KeePass) increases ...
2
votes
3answers
3k views

Microsoft password email reset link leads to different url?

...I am really annoyed and unsettled by the password reset email I just received from Microsoft. What should I think of this? My email client correctly told me that the underlying url is not the same ...
51
votes
5answers
8k views

Is sending passwords through cellphone text messages secure?

Both the sender and the receiver deleted the text after it was sent, but is it still possible that it exists somewhere and that someone can get to it?
3
votes
2answers
124 views

Obscure username input on login forms?

Not (necessarily) a duplicate of: Should both user ID and Password be masked for online banking? Definitely not a duplicate of: Should usernames be kept secret? I can sense your finger on the "mark ...
-2
votes
4answers
130 views

Getting password cracking time and byte storage from bruteforce?

I am stuck with this question, you can see it in the picture I have included below. PARTS (a and b) I know a-z will be 26^8, A-Z will be 26^8 guesses, and 0-9 will be 10^8 guesses. But I can't relate ...
0
votes
1answer
136 views

What can hacker do, if he knows my SALTED password?

for example, in any website (WORDPRESS or etc..) they store passwords in database, using SALT mehtod (as i know)... for example: $P$dfwegfwegewgIT03.wewefefweg if hacker got this password and ...
12
votes
3answers
5k views

Is a HMAC-ed password is more secure than a bcrypt-ed or scrypt-ed password?

Given an option , which one should I choose , a HMAC for storing a password securely or a bcrypt or scrypt library?
1
vote
3answers
86 views

Password reset question answer complexity

I need to implement a password reset feature for a system that will be controlled by a security question and answer pair. The problem is that I can't guarantee I'll have a valid e-mail address or cell ...
4
votes
3answers
1k views

Why do some websites force users to come up with difficult passwords?

I can't understand why we commonly force users to come up with difficult to remember passwords. * Your password must contain at least one number, one uppercase character, and one special ...
2
votes
2answers
244 views

Temporarily save failed logins password hashes for using against brute force attack

My question is about online brute force attacks, that try to authenticate in the website. 1) For the first case if the requests are coming from the same ip, I think this are relatively easy as after ...
0
votes
1answer
82 views

Different password for each login - based on some variable

This might sound a silly question, but I was thinking this as and extra option(which is not required) mainly for advanced users, who want to protect their accounts even more. Lets consider that other ...
89
votes
6answers
30k views

Password Hashing add salt + pepper or is salt enough?

Please Note: I'm aware that the proper method for secure password storage hashing is either scrypt or bcrypt. This question isn't for implementation in actual software, it's for my own understanding. ...