A hash buster is a program that generates a string of text for insertion in a spam message so that, to a spam filter, the e-mail appears to be a different message each time it is sent. The text might appear in the Subject line, its From line, or after the message body, and might either be coherent text or gibberish. The latter is sometimes arranged in word-like formations to be less easily detected.
The hashing process, used by some spam filters, represents each message as a single number (known as a hash) to simplify comparison. Each number is then compared to those of other messages to determine if it matches a list of known spam messages or enough other messages to determine bulk e-mail status. However, a hash buster is only effective for spam filters that rely solely on hash comparison, and most such programs combine a number of approaches.
More update follow: github.com
Features of Hash Buster:
PTH is a one of the hash buster attack technique that allows an attacker to start lateral movement in the network over the NTLM protocol, without the need for the user password. We evaluated a number of legitimate and illegitimate scenarios for (PTH) NTLM connections to see the differences and how each of these can be distinguished. Based on our findings, CyberArk Labs created a freely available tool (Ketshash) that detects live PTH attempts.
Hash Buster MD5 is hashing algorithm (one-way cryptographic function) that accepts a message of any length as input and returns as output a fixed-length digest value to be used for authenticating the original message.
MD5 has been deprecated for uses other than as a non-cryptographic checksum to verify data integrity and detect unintentional data corruption.
SHA – standing for secure hash algorithm used by certification authorities to sign certificates and CRL (certificates revocation list). Introduced in 1993 by NSA with SHA0, it is used to generate unique hash values from files. Developed as part of the U.S. Government’s Capstone project.
Since 2005 SHA-1 has not been considered secure against well-funded opponents, and since 2010 many organizations have recommended its replacement by SHA-2 or SHA-3. Microsoft, Google, Apple and Mozilla have all announced that their respective browsers will stop accepting SHA-1 SSL certificates by 2017.
According to Venafi, after January this kind of certificate use will cause major performance disruptions. For example, browsers will alert users that sites using SHA-1 are insecure and won’t display a green padlock or other symbol for secure HTTPS transactions. Browsers may even block access to sites that use the outdated certificates.
SHA-2 is a set of cryptographic hash functions which includes SHA-224, SHA-256, and SHA-512. The 256 in SHA-256 represents the bit size of the hash output or digest when the hash function is performed. Not all software supports every digest size within the SHA-2 family. Most browsers, platforms, mail clients, and mobile devices already support SHA-2. However, some older operating systems such as Windows XP pre-SP3 do not support SHA-2 encryption.
Many organizations will be able to convert to SHA-2 without running into user experience issues, and many may want to encourage users running older, less secure systems to upgrade.