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

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1answer
93 views

Is using OAuth for login less or more secure than maintaining your own passwords?

Pros: The complexity in managing passwords is maintained by a company with stronger security policy. Let's assume they secure passwords properly. The user doesn't have to maintain yet another ...
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0answers
29 views

How to analyze netstat for suspicious connections? [closed]

Somebody accessed my Microsoft account this morning and the IP that did it came from Thailand. A couple of days prior the incident, I noticed that my Command Prompt opened and closed immediately many ...
4
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2answers
197 views

How secure are these password schemes?

On One liner to create passwords in linux?, I see advice generally of the form head -c16 /dev/urandom | md5sum. They're all random combinations of text manipulation commands, sha1, base64 and md5sum ...
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2answers
98 views

Security concerns of running auto-login script on server-side?

I would like to fetch data from a website to do data analysis on a server. Username and password are required for login to the website. Therefore I will need to run an auto-login script on the server. ...
0
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1answer
1k views

How to avoid storing plaintext during CHAP authentication

When using CHAP authentication, passwords are stored in plaintext, then I used reversible encryption to store password. However, I recently found Citrix states " storing passwords using reversible ...
5
votes
3answers
105 views

Best practice for sharing a (.zip) file password with recipient

When sharing confidential documents, it's common to zip up and encrypt the files with a good password. However, all too often the file is emailed as an attachment with the password in the body of the ...
4
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3answers
580 views

Password strength metrics

In the question Source code as password I suggested using a combination of entropy and as @Lawtonfogle put it 'meatspace difficulty'. As suggested in the xkcd comic correct staple horse battery is a ...
6
votes
2answers
995 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 ...
27
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11answers
6k views

One liner to create passwords in linux?

How do you create a readable password using bash with one line? What if i'm looking for 128 bits of entropy? EDIT By readable I mean the 94 printable ascii characters (without space). It can use ...
1
vote
1answer
81 views

What are good password storage policies? [duplicate]

The world has progressed to the point where most of us have faulty memories and dozens of passwords to remember. What are good ways to solve this problem? I am interested in multiple answers and ...
1
vote
1answer
29 views

Passing a hash of a secret to a server instead of the plain text

Instead of passing an authentication token or api key in an http header to a server in the plain text, what if I calculated its hash and passed the hash? This way even if a adversary intercepts the ...
-1
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0answers
12 views

Would the fact an attacker knows you are using common words affect difficulty? [duplicate]

So I think we've probably all seen the famous "correct horse battery staple" XKCD comic: https://xkcd.com/936/ Now let's say that this becomes common practice for a lot of users, so an attacker has a ...
5
votes
1answer
104 views

Reviews of Argon2

I am not a security guy but just curious about the things here. I have seen several people in various answers here talked about the password hashing competition. Now that the winner is announced, I ...
7
votes
1answer
330 views

I stored a copy of my KeePass database on a portable hard drive and I lost the drive. Should I worry about that?

I've been using KeePass for years, and I have a lot of accounts. I need to access them anywhere I work, so I store one copy of my database on a portable hard drive. The drive isn't encrypted. The ...
39
votes
6answers
15k views

https security - should password be hashed server-side or client-side?

I am building a web application which requires users to login. All communication goes through https. I am using bcrypt to hash passwords. I am facing a dilemma - I used to think it is safer to make a ...
1
vote
2answers
81 views

Registration Email Hijacking

(Please read the update at the end) I am trying to find out how to send user registration emails securely. I read answers on this question: I don't intend to send passwords in emails, but I was ...
5
votes
2answers
150 views

Migrating password db off MD5 by chaining MD5 and Bcrypt?

I have a legacy system currently storing unsalted MD5 passwords. Unfortunately, some other controls are not in place (like the ability to expire passwords) and I'm trying to upgrade my algorithm to ...
2
votes
2answers
86 views

Are there any examples of huge damages done by password leaks, or bad password management policies? [closed]

Everybody knows that a strong password is very important. However, I can't find any citable public example of any kind where a user or users suffered a heavy loss from using bad passwords, or their ...
31
votes
5answers
2k views

Why do some sites block pasting into username or password input fields?

I use a few websites that prevent me from copying & pasting into the username or password fields. It's quite frustrating when using a password manager, and if anything I'd think it discourages ...
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votes
4answers
5k views

Why submit a website to plaintext offenders?

I've read this question and to quote from the accepted answer Besides that, by submitting the site to plaintext offenders, you will provide a third-party point of view, which might help your ...
0
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1answer
101 views

How does one securely create a MySQL database and user via the command line?

I'm making an app whose functionality includes creating a database and its user. This is accomplished like so: mysql -e "grant all on database.* to 'user'@'localhost' identified by '$PW';" $PW is ...
3
votes
2answers
85 views

What scenario are 'extra' strong passwords and hashing algorithms actually protecting against?

Note: I completely understand the need for strong passwords & I understand that there is an issue of speed with hashing. I am just interested in better understanding the actual negative impact of ...
18
votes
6answers
11k views

How can I avoid putting the database password in a perl script?

I have a cronned Perl script that connects to our database and does various kinds of lookups and integrity checks. The original script was written by someone long ago. My job is to make some changes ...
18
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6answers
4k views

How to avoid scripts with hardcoded password? [duplicate]

I have some scripts on Ubuntu Linux machine that logs in to a database server to run some maintenance daily. To login to the database, I need a password and right now it is hard-coded in the script. ...
7
votes
2answers
223 views

How to securely store and manage one-time backup codes for 2FA?

I am already using 31 services with 2nd factor authentication and the number is growing. In addition to having multiple authentication devices, I decided for or had to generate a separate set of ...
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2answers
160 views

Simplest way of hashing a password with multiple different hash algorithms [closed]

I have a list of plaintext passwords that I would like to hash with various different hash algorithms (for educational purposes). As a minimum I would like to obtain hashes under MD5, SHA1, SHA256, ...
0
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2answers
171 views

Hashed master password and generated encryption key in a password manager program

I'm writing a WPF password manager application to practice programming, so far this is the scheme I intend to use to store master password and individual site password: Master password: Generate a ...
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5answers
588 views

Why can passwords be used to encrypt data, but are less strong for authentication?

Encryption software is often password based. Even if the adversary gets your computer they can't get the data without knowing the password, and bruteforcing is infeasible. Websites use passwords to ...
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1answer
39 views

How many possible randomly generated salts could be generated using PHP's password_hash() function?

I have two questions here: 1) How many possible randomly generated salts could be generated using PHP's password_hash() function? 2) According to php.net it states that the return value is a ...
10
votes
2answers
12k views

How weak is MD5 as a password hashing function ?

A professor told us today, that MD5 is weak. I understand his chain of thought but pointed out, that IMHO MD5 is a good way to go if you would use a long (even really long) dynamic salts and static ...
40
votes
3answers
4k views

Security Review - password_hash implementation for PHP

I'm currently working on a "helper function" for PHP's core to make password hashing more secure and easier for the majority of developers. Basically, the goal is to make it so easy, that it's harder ...
2
votes
1answer
93 views

Recover password from .pfx file

I have an old Windows SmartClient application that is published with a signed certificate (a .pfx file). We want to extend the expiration date to more than one year. I've used a program called ...
10
votes
5answers
12k views

Regulations that specify password length?

I have read: PCI DSS 1.2 SOX 404 AR 25-2 ISO 27001 But only PCI DSS specifies a minimum password length. Are there any other regulations that dictate password lengths for any industry? NIST ...
1
vote
1answer
70 views

Password sent over TLS: threats other than TLS compromise?

One of my findings during a security audit was a password, sent as is over the network. As bad as it sounds, this happens only over HTTPS connection. Some authors suggested here that additional ...
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3answers
97 views

Why shouldn't I use an old password? [duplicate]

Some services like Google or Facebook forbid me to use a password that has already been use for the same account in the past. My question is, if this old password was never compromised (i.e it was ...
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votes
0answers
89 views

Enter the 1st 3rd and 12th character of your password [duplicate]

Some businesses such as banks and insurance companies ask for specific letters of your password. For example a bank asks for the 1st, third, and 12th character of your password. Would this be less ...
54
votes
11answers
43k views

Are password-protected ZIP files secure?

Following my answer. If I can list contents of a 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 ...
7
votes
1answer
85 views

What's the most secure way to circumvent encryption to enable password recovery?

I have a web app (which I've talked about here before). Users can use it to save people's contact details. These contact details are encrypted to ensure that they are difficult to get at if they're ...
6
votes
3answers
184 views

Authenticating a user via SMS

I'm involved in a project that's building a chat-bot that users can communicate with via SMS from their mobile phones. We'd like the users to be able to use the bot to do some basic account-management ...
9
votes
1answer
129 views

Handling “forgot password” functionality with encrypted data without security questions

As a sort of follow-up to this question on handling password-reset functionality when dealing with encrypted user data, is there any good method for resetting a user's password in an encrypted web ...
24
votes
5answers
989 views

Would turning a Diceware phrase into a sentence decrease its security?

Diceware passphrase lengths are on the rise - up to six or seven words now. The old adage that passphrases are easier to remember may be true for shorter phrases, but six truly random words can be ...
80
votes
10answers
9k views

Is there a threshold for a password so long it doesn't get any more secure or even becomes insecure?

I always hear "A long password is good, a longer password is better". But is there such a thing as a "Password is so long it is becoming unsafe" or "Password is long enough, making it longer won't ...
822
votes
23answers
162k views

XKCD #936: Short complex password, or long dictionary passphrase?

How accurate is this XKCD comic from August 10, 2011? I've always been an advocate of long rather than complex passwords, but most security people (at least the ones that I've talked to) are ...
20
votes
4answers
1k views

When encrypting cloud-stored data, is it acceptable to use the user's account password?

I'm developing a web service that stores sensitive personal information (such as telephone numbers, addresses, full names, and email addresses) in a database, such that it can be accessed from ...
41
votes
12answers
11k views

Is it good practice to send passwords in separate emails, and why?

I have heard from different people and in different places that if I send an encrypted file to someone else, I should send them the password in a separate email; but why? If someone is sniffing, they ...
3
votes
5answers
240 views

Recommended level of password complexity for Keepass

I want to start using a Keepass master password that I can easily remember. Let's take this sentence: I really hate blue mountains, and let's make it one password: ireallyhatebluemountains. Is this ...
7
votes
2answers
215 views

Is it easier to crack a ZIP file than a 7z archived file given they have the same password?

I am interested in knowing if either of them is easier to crack than the other because of inherent flaws.
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2answers
88 views

Is it good to store passwords in a separate table/database and manage them in a separate process?

I'm quite a newbie at systems architecture and security so I just want to check that this plan makes sense. I'm building a web app and I need to store a password for each user. I've already read ...
2
votes
2answers
106 views

Where to store a pepper?

Assuming you're using a pepper in your password hashing, where should it be stored? I know you shouldn't store it in the database since it can easily be found there during a dump and the idea is to ...
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2answers
74 views

Creating secure passwords [duplicate]

I have been tasked with writing a random password generator to be used on a series of throw away accounts. In this scenario, the accounts need to be very secure and will be deleted after a single day ...