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Hashing Algorithms

A cryptographic hash function is a mathematical formula or algorithm that creates a one way encryption process. By “one-way”, this means the information that is encrypted by a hash function can not be decrypted. The purpose for using these one-way hashing algorithms is two-fold: to provide a check of integrity to protect some important piece […]

Witness Signatures Add Authenticity

Part of the Apple/FBI court case involves how software updates are protected with digital signatures. The key ensures that the update comes from Apple and therefore has a level of trust associated with the history of the company. The government is not asking Apple to turn over the signing key and Apple is not likely […]

Hacking an Encrypted Phone

Recent news has the media atwitter with misinformation about hacking phones and encrypted data. Here are some of the basic issues: ENCRYPTION Encryption is the process of using a coding technique to obscure information. Simple substitution techniques like using a number for each letter of the alphabet have been in use for many years. These […]

Journal Signatures Use Merkle Trees of Hashes

In the world of business transactions, there is a constant need to maintain logs or journals of transaction history. These journals need to be able to be validated for their integrity over time and they often need to be publicly available. Here are some examples of common transaction journals: Monthly bank statement for checking or […]

Password Cracking

Generally, password cracking takes place in the ENTRENCH phase of the attack, after an initial penetration has been successful and password hashes have been retrieved from the compromised system, but it can be done at any point if it will yield results and hashes are available. The attacker will probably need admin/root level access, but […]


Ophcrack is a free and open source tool that can be used either within an existing OS (linux, Windows, OS X) environment or as a live-CD that boots its own version of linux. Either way, it has the ability to retrieve Windows password hashes and crack both LM and NT versions using a set of […]

john the ripper

John the ripper is a password hash cracking tool that is available free for both unix/linux and Windows platforms. It autodetects the type of hash and by default uses a hybrid approach of dictionary and brute force attacks to attempt to crack the hash as quickly and efficiently as possible. It can use a wide […]