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

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42
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5answers
4k views

Is it safe to tell your users what kind of hashing algorithm you use?

For example, on the user registration page, is it safe to tell people "Your password will be stored as a one-way hash using the (whatever) algorithm."
4
votes
3answers
126 views

Is it good practice to SHA512 passwords prior to passing them to bcrypt?

I want to allow any-sized passwords to be allowed to be submitted. I currently use bcrypt as a key derivation function for passwords, however I have realized that it has a maximum input length of 72. ...
0
votes
2answers
207 views

Storing multiple hashes to prevent collisions, security risk?

This is all just for curiosity's sake, so discussion on which hashing algorithm is harder/better/faster/stronger is irrelevant. But my question/thought is this.. With regards to password storage, and ...
1
vote
0answers
70 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 ...
1
vote
2answers
73 views

In two step authentication, should I check step 1 before proceeding to step 2 or check both at the end?

I asked this question first on Stack Overflow but it was suggested that Information Security would be a better place for it (pretty obvious in hindsight). ...
-1
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4answers
71 views

Is salted MD5 or salted SHA considered secure?

Is using something like bcrypt or scrypt necessary? The hashes are so much longer to store in a database. Can one get away with using salted MD5 or SHA and still be secure?
3
votes
7answers
132 views

Is providing a website password over the phone any less secure than other identifying information?

I've been dealing with two separate banks for completing a 401k rollover (I do not have any other accounts with either of the two banks), and I've encountered something with both that I've never seen ...
0
votes
2answers
63 views

In addition to using strong hash algorithms, what is a good “password requirement”? [duplicate]

Assuming the use of bcrypt/scrypt: Would it be a good idea to "require" a password of at least 12 characters, also mentioning the possibility of using long passphrases, instead of your typical ...
2
votes
2answers
261 views

Is upgrading key-stretching algorithms and/or repetitions a thing?

Consider back in the 90s you're ahead of the curve, you hashed and salted your passwords with SHA, and you're a big site, millions of accounts, etc. Well the web evolves, and over time more advanced ...
18
votes
4answers
3k views

Is it a security concern that a shop I registered at obviously does not encrypt my password?

I was kind of shocked when I just received my confirmation mail from the shop where I just registered myself: they sent my username (which is my email address) and the password I typed in. The ...
1
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6answers
204 views

Why not use weak passwords?

In a specific situation: online stores that cannot possibly store payment details because you pay using paypal, but require registration. What reason is there to use good passwords here? Breaking ...
21
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3answers
4k views

Doesn't plaintextoffenders.com just provide attackers with a good list of sites to attack for passwords?

On the face of it, PTO seems like a good idea in educating people about password security. On the other hand, if I were an attacker, PTO would be the first place I would start if I wanted to start ...
2
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4answers
179 views

Should we rethink our entire password strategy? [closed]

Passwords get discussed a lot on this site, and there's quite a lot for both users and sites to do, to stay in line with "best practice". Web sites need a password strength policy, account lockout ...
10
votes
3answers
917 views

What is the risk and mitigation of accidentally typing a YubiKey password in an open forum?

I have a YubiKey in my laptop (for testing) and accidentally broadcast my YubiKey password out to the Internet. Since this is only a test key, and has no access to anything of value, here are some ...
4
votes
2answers
57 views

Should password recommendations be different for devices, networks, and internet?

I started using a password manager last year and updated nearly all of my internet accounts to super-strong, unique passwords, and that isn't a problem, cause I only access them from web browsers or ...
10
votes
4answers
963 views

Does the strength of password matter in bcrypt?

Even if I choose 1 character for my password or 32 characters with numbers, letters, uppercase symbols etc. the bcrypted password will still be 60 characters length password. So does the password ...
26
votes
5answers
5k views

Length of passwords that are rainbow table safe

With large computing power (like what you can get in the Amazon cloud for example) you can generate huge rainbow tables for passwords. There also seems to be some large rainbow tables reachable that ...
2
votes
1answer
60 views

Identical lanman hashes on AD accounts?

I ran metasploit's smart_hashdump module against my (2008r2) domain controllers, trying to find any accounts that may still have lanman hashes in place. These should have been disabled long ago. I'm ...
4
votes
3answers
346 views

comparing password hashing algorithms - PoC ideas?

OK so I just started working for a security consulting firm and we recommend SHA 256 (with salt) for password hashing because MD5 is too weak. I have read some brilliant answers (the list is too ...
1
vote
0answers
37 views

Security for message queue in ActiveMQ

I am using ActiveMQ and WSO2 for my application. I need to protect my queue to restrict posting of messages by anonymous users(I need to protect my queue with some password). I know, there is a ...
1
vote
2answers
64 views

Are repeating random patterns weaker than non repeating random patterns?

Which would be harder to crack: a password comprising of n characters randomly selected or a password comprising of x randomly selected characters repeated m times so that m*x=n. For example: ...
2
votes
2answers
4k views

Is it possible to brute force all 8 character passwords in an offline attack?

This article states: Brute-force techniques trying every possible combination of letters, numbers, and special characters had also succeeded at cracking all passwords of eight or fewer characters. ...
0
votes
2answers
52 views

how long do lowercase alphabets-only passwords have to be to match more complex ones? [duplicate]

Lowercase-only passwords are convenient for phones since we dont hit shift or go to characters page(each which is as much effort as hitting a character in my Android devices). But how long would a ...
0
votes
2answers
60 views

Timing-safe string comparison in high-level languages

I'm looking for a reliable solution to compare two strings without leaking their content through time differences. The length of the strings is not secret. The background is this: I'm implementing ...
3
votes
2answers
109 views

MySQL ENCRYPT salt is not random?

I know there's little reason to still use ENCRYPT() nowadays, what with bcrypt being almost ubiquitous and MySQL providing better hashes such as SHA1. But while dabbling with ENCRYPT() on MySQL ...
30
votes
9answers
2k views

Is there a method of generating site-specific passwords which can be executed in my own head?

I was thinking recently about password security. My goal is to have mostly random passwords, that are different for each site. But you also should be able to remember them (or re-generate them) ...
3
votes
1answer
328 views

Decrypt Passwords based on using a user's password

I am creating a database to store our client's information at work (a heritage center specializing in DNA based genealogy). Once the results of a test come back, we have people that use the ...
0
votes
1answer
67 views

How can I tell if my ISP account password is encrypted?

How can I be sure my ISP encrypts my account password? I found out accidentally that mine did not. I had called to report an interruption in service, and in the process of "troubleshooting", the ...
2
votes
6answers
3k views

Hardware USB Key to Reset Any Windows Password

This tool requires physical access of course, and there are many things you can do once you have physical access, but this peaked my curiosity. The tool in question: ...
8
votes
4answers
2k views

How secure is NOPASSWD in passwordless sudo mode?

On all our boxes we have ssh access via keys. All keys are password protected. At this moment the sudo mode is not passwordless. Because the number of VMs are growing in our setup, we investigate the ...
42
votes
9answers
5k views

Can users make use of a password manager when banks tell them never to write passwords down?

Consider a user who wants to use a password manager for their banking passwords. Advice from banks usually says they should never write down their password. The user would be concerned about going ...
9
votes
3answers
903 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 ...
303
votes
12answers
48k views

What technical reasons are there to have low maximum password lengths?

I have always wondered why so many websites have very firm restrictions on password length (exactly 8 characters, up to 8 characters, etc). These tend to be banks or other sites I actually care about ...
4
votes
3answers
462 views

Is piping a `ssh-agent` signed message as a password secure?

There's an encrypted filesystem on a server I ssh into using public key authentication. Since a forwarded ssh-agent can deterministically sign a message (see also the ssh-agent protocol section ...
0
votes
1answer
96 views

How do I generating a word list from a known seed word?

I've lost my master password. Not all is lost as I know the original word that generated the password: It was generated by a random case switching for consonants and random vocal to numbers. For ...
1
vote
3answers
105 views

Issuing password information by phone [duplicate]

We have a confidential portal for clients. Historically they have been identified face to face in person and handed a unique token number that is associated with their email address and allows them ...
1
vote
2answers
118 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
vote
1answer
262 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
votes
6answers
15k 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
votes
1answer
109 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
vote
1answer
43 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
vote
3answers
257 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
votes
0answers
26 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
votes
4answers
183 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
votes
1answer
51 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
votes
2answers
4k 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
vote
1answer
74 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
votes
2answers
156 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 ...
1
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1answer
77 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
104 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: ...