a cryptographic hash function with a 128-bit (16-byte) output, now deprecated

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How were shift amount constants in MD5 found? [migrated]

The md5 specification gives a series of 4 rounds to execute over a 16-word block. Each round has a repeating sequence of 4 shift amounts (s in [abcd k s i]) : 7, 12, 17 and 22 for the round 1 5, 9, ...
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1answer
63 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 ...
2
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2answers
72 views

How secure is a MD5 hash of an 128bit key

Apparently, for the Android KeyChain an encrypted master key is stored along the MD5 hash of the unencrypted Key. How secure is that? MD5 is known to have collisions, but I guess we can assume with an ...
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1answer
139 views

Someone help me decode this [closed]

What type of hash is this? a9df6dcd35f4e7223ff3dd087abcc266 I can't find anything when I decrypt it. Please someone decrypt it
1
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1answer
61 views

Multi hash security [duplicate]

Is md5(sha1(pass)) more secure than md5(pass)? For example in case of sqli when attacker cant get our hashing schema, brute force or dictionary attack would be much less efficient. Am i right or is it ...
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0answers
141 views

oclHashcat error messag in Kali Linux

I am in the process of learning oclHashcat syntax. Currently, I am working on breaking a file of md5crypt strings with a dictionary file. The dictionary I am using is rockyou.txt from an installation ...
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0answers
391 views

John the Ripper - Calculating brute force time to crack password

I'm using incremental mode (brute force) mode in John the Ripper to crack Linux MD5 passwords. I'm trying to calculate the time it will take to run through all combinations of 12 passwords (with 12 ...
1
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1answer
263 views

How strong is PDF security/encryption?

I want to securely convey a PDF document containing sensitive information from my system to another system. The latter is operated by a different person, whom I trust. However, this person does not ...
1
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0answers
90 views

Can't see advantages of rainbow tables over hash tables [closed]

I've read about rainbow tables (which I've confused with hash tables at first). I understand that it uses a reduce function R(x) and by saving start value P(plaintext) and ending hashed value H I can ...
3
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2answers
172 views

How safe is to secure sensitive content by URL with MD5 hash and no other authorization?

Suppose we have website that use MD5 hash in URL like this: http://somewebsite.com/XXX/ where XXX is MD5 hash. Content of this website may have sensitive information like transaction details with ...
0
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1answer
67 views

Good way to make a secure token for logged out users

I work for a firm that has a marketplace on the web. We want to make a link with a token that stops an ad on the marketplace without the user being logged in. Someone suggested that we make a token ...
2
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4answers
547 views

Is hashing the hash considered an extra level of security [duplicate]

As in md5(md5(md5(x)))... I can remember coming across that in some piece of code. If the attacker can somehow reverse md5(md5(md5(x))) into md5(md5(x)) then he certainly can reverse md5(md5(x)) into ...
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2answers
129 views

Difference between OS X md5 and gnu md5sum

I have installed the "md5sum" utility on my Mac and there was also a "md5" binary pre-installed in /sbin. My problem and question is this: "Isn't MD5 a standard algorithm?" Because I get different ...
0
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2answers
77 views

Is there any reason to send file checksum for signed, encrypted files with MDC

I am using OpenPGP and sending a signed, encrypted file with forced MDC (Modification Detection Code) over the network. In typical file transfer scenarios where security is not in picture, an md5 ...
2
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2answers
195 views

injected code decode

Recently I saw a domain of mine was hacked and the hacker have injected his code in some encryption format as below. <?php $l___l_='base'.(32*2).'_de'.'code';$l___l_=$l___l_(str_replace("\n", '', ...
4
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1answer
94 views

MD5 security concerns in download verification

The MD5 hashing algorithm is known to be vulnerable to collisions for a number of years now, see its Wikipedia entry. Still, I see that in many places throughout the web, MD5 is used to verify ...
1
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2answers
147 views

Ip4v Rainbow Table [closed]

a friend challenged me to find out the ip from the new web server he uses. Is there a rainbow table or something similar with all possible adresses or are 4 billion numbers to much for a normal ...
0
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2answers
167 views

What is the collision likelihood of MD5 when non-numeric values are removed?

Start with a unique identifier String macAddress = "CC:3A:61:24:D6:96"; Hash the identifier via MD5 implementation String hash = md5(macAddress); //bd37f780e10244cf28810b969559ad5b Remove all ...
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2answers
928 views

Reversible Hash Function?

Is there any reversible hash function? The hash function like SHA and MD5 are not reversible. I would like to know if there exist some reversible hash functions?
3
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3answers
430 views

Client-side hashing of password before sending it from login form [duplicate]

I have just realized, that my web application is sending unencrypted passwords from login form. It's just like that -- I've analysed, that string sent by user from login form is hashed with MD5 (which ...
1
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1answer
666 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)?
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4answers
247 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?
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1answer
347 views

The brute-force resistence of bcrypt versus MD5 for password hashing?

Can anyone give me an idea? Assume the salt(s) is/are known. For example, if I have a $k$-character long password that is hashed in MD5 versus bcrypt, is there a way to estimate how much more time it ...
0
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2answers
107 views

Is a long salt usually sufficient for security purposes, even with MD5?

I always hear that MD5 is too fast for effective password crypto because you can crack up to 6 characters very quickly (or is this number higher now)? But what if the salt you use is really long and ...
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1answer
140 views

What are the enhancements of SHA1 compared to MD5?

I am looking for enhancements of SHA1 when its compared to MD5. But I am not talking about just heap sizes. I am talking about different enhancements than heap size. Also, I think md5 is faster than ...
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2answers
159 views

If md5 is only insecure because of its speed, why doesn't this workaround make it reasonably secure?

I'm going to preface this by saying I have absolutely no clue when it comes to cryptography, but I'm posting this question because I'm very interested and I have no doubt there are some smart people ...
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1answer
274 views

Security weaknesses in using RSA encrypted MD5 hash of certificate content

Suppose you have an Internet banking site based on a secure web server running the HTTPS protocol via port 443. The server authenticates itself to clients through an X.509 certificate signed by a ...
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2answers
503 views

Can NSA generate all hashes for rainbow table to break md5?

I was wondering about md5 encryption. It is good, and I agree that it is unbreakable. But this is why we have rainbow tables. What if bunch of people gather together and start brute forcing and ...
2
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1answer
157 views

How fast can a MD5 collision be found

If I have a salt of 16bytes and 16bytes of data, how fast can one find another 16bytes of data so that MD5(salt + data) == MD5(salt + other data)? I don't expect an answer accurate to the nanosecond, ...
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1answer
132 views

Is hashing a DLL useful to protect from DLL hijacking?

I want to make sure that the dynamic link libraries used by my application can't be replaced with other libraries of the same name, in order to inject malicious code. Therefore, I thought about ...
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2answers
297 views

Which hashing algorithm is ideal for use on the web? [duplicate]

I am new here, and have poked around the site looking for an overview of which hash algorithm to use on the web and why. It seems to be the consensus that SHA-256 or other SHA-2 family algorithms are ...
55
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3answers
19k views

How can I create a password that says “SALT ME!” when hashed?

How can I create a password, which when directly hashed (without any salt) with md5 will return a string containing the 8 characters "SALT ME!". The hope is that a naive developer browsing through his ...
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4answers
2k views

Why does MD5 hash starts from $1$ and SHA-512 from $6$? Isn't it weakness in itself? [duplicate]

I have moved this question from stackoverflow to this place. I know it may be a question about 'opinion' but I am not looking for a private opinion but a source of the final decision to keep it this ...
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3answers
117 views

Cryptosytem Question [closed]

A file is encrypted and placed on a secure FTP server. An MD5 hash is taken of the file and also placed on the FTP server. A userlogs in to the server and downloads both files, however, the hash fails ...
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1answer
203 views

Is using MD5 in NTLMv2 protocol to store Windows passwords is secure?

I read that Windows (probably not new OSs but say, Windows Server 2008) stores passwords using Hashes using NTLMv2 protocol which uses MD5 hash function. My questions: MD5 is known to be insecure ...
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3answers
1k views

Email activation string with MD5'd random number and email secure?

For the registration on my PHP powered website, I require email confirmation. After a user registers, a string is generated with the following code and sent to their email address. $key = ...
1
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3answers
141 views

Authorization with MD5 imlemented in Javascript

I want to use MD5 function (JavaScript library) to hash password before send it to server during logging in to website and during registration proces. I want to ask is it a secure method? I can't ...
3
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1answer
350 views

Cracking DES(Unix)/MD5 ARP

This is a basic exemple of Unix Pass Encryption. I have little Hash of MD5 ARP : user50:$apr1$w7YNTrjQ$0/71H7ze5o9/jCnKLt0mj0 user60:$apr1$AIw2h09/$Ti0TRlU9mDpCGm5zg.ZDP. I need to find the pass ...
3
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2answers
2k 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 ...
0
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1answer
152 views

Is it possible to insert data into UUID?

Is it possible to insert arbitrary data into UUID? Let's suppose we have an MD5\SHA hash of something... can we encode that data into a valid UUID?
0
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1answer
219 views

MD5 Algorithms in web development

I am storing the passwords of my college website in our own server. I am storing the passwords using the MD5 encryptor. But the doubt I got is since the decrypter is there I can also decrypt the ...
0
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1answer
224 views

company is sending md5 string via GET['password'] dangerous?

So, this big, reknown company (you all heard off) is sending md5 encrypted strings (with GET key: password) over HTTP. I accidentally came over it since I wanted to use jnlp on a non-windows ...
7
votes
1answer
692 views

Does bcrypt on top of md5 reduce its security?

A GitHub project I recently checked has a flawed security as they're using an unsalted md5() to hash the passwords. I opened a bug and they acknowledged it. However, the transition from md5() to ...
4
votes
2answers
688 views

Is HTTP Digest + MD5 still an alternative to consume my own api?

I'm reading a lot about implementing security constraints to a REST API. There are a lot of methods, some better than others for 3party applications or to consume my own API. HTTP Basic + TLS (with ...
1
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1answer
3k views

John the ripper passwd file format with salt not working

I'm trying test password strength in one of our e-commerce sites. I'm using john the ripper to brute-force a password file. The algorithm used by PHP is: $hash = md5($salt . $pass) No other ...
3
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2answers
528 views

Does PCI ban using MD5 to store sensitive data?

Just had a vendor tell me that because their PCI auditors did not recommend banning the use of unsalted MD5 to store sensitive data at this time with with their current level of PCI compliance that ...
7
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1answer
782 views

Is Postgres password-based authentication secure?

According to Postgres's documentation, Postgres's password authentication method uses MD5 hashing to secure the password: The password-based authentication methods are md5 and password. These ...
2
votes
1answer
247 views

Unknown encryption string [closed]

I'm trying to learn about encryption and decryption methods when I faced this string: {MD5}JfnnlDI7RTiF9RgfG2JNCw== MD5 is 16-byte string, so anyone know what type of encryption is this and why ...
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1answer
80 views

What is wrong with those calculations md5 gpubruteforcing

I read an article by a stackexchange founder: http://www.codinghorror.com/blog/2012/04/speed-hashing.html It talks about: " two ATI Radeon 7970 cards generating nearly 16000 M c/s with MD5." " the ...
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1answer
287 views

Encryption algorithm encryptable by md5 of key and decryptable by key [closed]

Is it possible to make an encryption algorithm that can be encrypted by the md5(or any other one way encryption algorithm) of the key and decrypted by the key? The purpose of this would be for the ...