Linked Questions

809
votes
12answers
220k 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 database,...
590
votes
5answers
236k 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 ...
48
votes
11answers
11k views

Why are only passwords hashed?

I just learned a few things about hashing algorithms – MD5 and SHA-1. So, if I am not wrong passwords are hashed so that in a rare situation of your database being compromised a hacker can not see all ...
78
votes
4answers
19k views

How long will it take to crack the passwords stolen in the Yahoo hack announced 14 Dec 2016?

Apparently Yahoo was hacked yet again with up to a billion user accounts being compromised. The article says Yahoo uses MD5 for password hashing. Are the hackers likely to be able to crack the ...
16
votes
2answers
36k 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 ...
21
votes
3answers
9k views

MySQL OLD_PASSWORD cryptanalysis?

The password hash used for MySQL passwords prior to version 4.1 (now called OLD_PASSWORD()) seems like a very simple ad-hoc hash, without salts or iteration counts. See e.g an implementation in ...
4
votes
4answers
16k 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?
1
vote
2answers
4k views

How can this website crack MD5 hashes? [closed]

I have heard that hashing, such as MD5, is one-way and cannot be cracked. But there are some websites that can decrypt hash, like www.md5hashing.net and some scripts like findmyhash.py. I tested some ...
15
votes
1answer
9k views

HQL injection example

Our developers left a surprise in handling user login. Namely: // java List users = hibernate.find("from Users where username = '"+formUsername+"'"; if (users.length==0) { return BAD_USER; } if (!...
8
votes
3answers
1k views

Is Using MD5 Sufficient Reason to Reject This Payment Processor?

I'm evaluating a credit card processor[1], and I noticed they are using MD5 as part of a salted hash algorithm to protect a secret key. Since I know MD5 is generally considered broken, this feels like ...
6
votes
1answer
5k views

Is possible to force a file to generate an specific MD5 signature?

Sometimes MD5 is used to validate that a downloaded file is really valid. So I want to know if is possible for a hacker to modify a file and introduce some malicious code AND make that file generate ...
4
votes
1answer
7k views

Cracking MD5 passwords with the same salt

How long would it take to crack passwords up to 10 letters long if you knew the hashes were MD5 with a salt (that you know)?
1
vote
2answers
4k views

Tool for generating MD4 collisions

There are a lot of research papers available online that discuss vulnerabilities of MD4 algorithm, but I couldn't find any implementation of these. Uptill now I have used tools like John the Ripper ...
4
votes
4answers
2k views

CISCO IOS service password-encryption

In Cisco IOS there's the service password-encryption command to encrypt all passwords in the config file to prevent unauthorized individuals from viewing them. quoting from http://www.cisco.com/c/en/...
2
votes
2answers
502 views

MD5 brute force on a faulty hash?

MD5 for passwords is considered insecure due to the ability to brute force and pick up the result. But what if I change some characters of an MD5 hash and I keep a record of that change so that ...

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