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New 25-GPU Monster Devours Strong Passwords In Minutes

chicksdaddy writes "A presentation at the Passwords^12 Conference in Oslo, Norway (slides), has moved the goalposts on password cracking yet again. Speaking on Monday, researcher Jeremi Gosney (a.k.a epixoip) demonstrated a rig that leveraged the Open Computing Language (OpenCL) framework and a technology known as Virtual Open Cluster (VCL) to run the HashCat password cracking program across a cluster of five, 4U servers equipped with 25 AMD Radeon GPUs communicating at 10 Gbps and 20 Gbps over Infiniband switched fabric. Gosney's system elevates password cracking to the next level, and effectively renders even the strongest passwords protected with weaker encryption algorithms, like Microsoft's LM and NTLM, obsolete. In a test, the researcher's system was able to generate 348 billion NTLM password hash checks per second. That renders even the most secure password vulnerable to compute-intensive brute force and wordlist (or dictionary) attacks. A 14 character Windows XP password hashed using LM for example, would fall in just six minutes, said Per Thorsheim, organizer of the Passwords^12 Conference. For some context: In June, Poul-Henning Kamp, creator of the md5crypt() function used by FreeBSD and other, Linux-based operating systems, was forced to acknowledge that the hashing function is no longer suitable for production use — a victim of GPU-powered systems that could perform 'close to 1 million checks per second on COTS (commercial off the shelf) GPU hardware,' he wrote. Gosney's cluster cranks out more than 77 million brute force attempts per second against MD5crypt."

2 of 330 comments (clear)

  1. Re:Use different passwords for different things by DrXym · · Score: 5, Informative
    Different passwords for different things is a good idea.

    But the issue is not brute forcing over the network. The issue is hackers stealing a database of passwords, then bruteforcing the lot of them locally. Some sites don't even bother to hash the password at all and some don't salt them or use a weak hash. So if the database is lifted, the hackers could potentially recover some or all of the passwords with little or no effort. So if you use the same email and password for an insecure site as a strong site, you are trouble.

    Therefore it would be wise to arrange sites into tiers of importance. Tax / health / social security on the top. Then banks. Then cloud / email services. Then stores. Then sites with personally identifying info. Then forums and other throwaway crap. For each tier take appropriate measures to ensure uniqueness of the password and login id and use password safe to manage this mess. On the bottom tier, you could probably use the same throwaway password for every site, or a variant of it (e.g. tack on the first 4 letters of the domain host) since a compromise is a nuisance rather than as a threat.

    And use something like Password Safe so you don't have to remember all this crap.

  2. Re:my password by AftanGustur · · Score: 5, Informative

    To all you gloom and doom people out there, here's my suggestion. If your password is monkeys1459, change it to monkeys1459monkeys1459. That's 22 letters and equally memorable.

    You are assuming that the password test function doesn't text the pattern XX i.e. the same string repeated.

    Password crackers actually test a number of permutations, like adding every digit 0-9 to the end of the string, reversing the order of characters, setting the first letter to uppercase, setting all the letters to uppercase, AND, repeating the password.

    So your little "trick" is already outsmarted by today's password crackers.

    --
    echo '[q]sa[ln0=aln80~Psnlbx]16isb572CCB9AE9DB03273snlbxq' |dc