Personally, I would not recommend using a hash for a password because there are databases that store hashes that result in a very small password such as that...
EG
www.crackstation.net
CrackStation uses massive pre-computed lookup tables to crack password hashes.
They keep hash database of passwords. Still they are not using SHA-3 (512bit).
Even if they have SHA-3 (512bit) hash database it won't work.
If i used "cat" as password then it would be very easy to crack. But i am using the hash value "B2FAF80C85BD36029DC3F804CBF439888FD1CA195AB0E3DECB872F8AA9EF767E4866186EBB8B5ECFA1237147A94775F8302648BE0FD0AE3A6EBBDF931F423360" as password. So normally they will be searching for hash value of this password, which will be "F1650CB4543DCC9E4B855541054295F43DE0CADAB9071D96187119855E136E743CE855E143258ED05348682416231CB7178A554D577B25600463DA21AEFA10EF" if SHA-3 (512bit) is used . They will never find the match.
How about doing multiple hash?
hashing "cat" gets "B2FAF80C85BD36029DC3F804CBF439888FD1CA195AB0E3DECB872F8AA9EF767E4866186EBB8B5ECFA1237147A94775F8302648BE0FD0AE3A6EBBDF931F423360"
hashing "B2FAF80C85BD36029DC3F804CBF439888FD1CA195AB0E3DECB872F8AA9EF767E4866186EBB8B5ECFA1237147A94775F8302648BE0FD0AE3A6EBBDF931F423360"
gets
"F1650CB4543DCC9E4B855541054295F43DE0CADAB9071D96187119855E136E743CE855E143258ED05348682416231CB7178A554D577B25600463DA21AEFA10EF"
hashing "F1650CB4543DCC9E4B855541054295F43DE0CADAB9071D96187119855E136E743CE855E143258ED05348682416231CB7178A554D577B25600463DA21AEFA10EF"
gets
"AE7F5C8C097A0F2C217BDF86F1992070D419C3E3DC6A90BA8A0C517716E9C3C1AB23D7E50FF248D2C78F4309B1C5F63A34FC5355F60B7BBD3EDFE4B330419684"
this final hash value will be used as password.
user needs to remember three things
- Easy word "cat"
- The hash function SHA-3 (512bit)
- Number of times hash was done : 3
Anyone trying to crack it using general method will fail, unless he knows all the three thing mentioned above
what if i concatenate all three hashes to get even more lenghty password : "B2FAF80C85BD36029DC3F804CBF439888FD1CA195AB0E3DECB872F8AA9EF767E4866186EBB8B5ECFA1237147A94775F8302648BE0FD0AE3A6EBBDF931F423360F1650CB4543DCC9E4B855541054295F43DE0CADAB9071D96187119855E136E743CE855E143258ED05348682416231CB7178A554D577B25600463DA21AEFA10EFAE7F5C8C097A0F2C217BDF86F1992070D419C3E3DC6A90BA8A0C517716E9C3C1AB23D7E50FF248D2C78F4309B1C5F63A34FC5355F60B7BBD3EDFE4B330419684"
this is 384 character password. it cannot be found in any database. Obviously it cannot be cracked.
hashing "cat" ten times using SHA-3(512 bit) we get hashes
cat
- B2FAF80C85BD36029DC3F804CBF439888FD1CA195AB0E3DECB872F8AA9EF767E4866186EBB8B5ECFA1237147A94775F8302648BE0FD0AE3A6EBBDF931F423360
- F1650CB4543DCC9E4B855541054295F43DE0CADAB9071D96187119855E136E743CE855E143258ED05348682416231CB7178A554D577B25600463DA21AEFA10EF
- AE7F5C8C097A0F2C217BDF86F1992070D419C3E3DC6A90BA8A0C517716E9C3C1AB23D7E50FF248D2C78F4309B1C5F63A34FC5355F60B7BBD3EDFE4B330419684
- CBBA91B52162FE79666609C0178C3AD043837EA95FBF30D5834D30B7FC4A7C5CC85B040B7DCDEAAAB24EB4DA030A22EC9C3E40B5377C99C1DEAA894970934D09
- 208385B1E83A6879D10B274B8A42ADF9E54D515D9B14FB8FC939A39B0A38B1BE61DDEEBDA31845EACAE3BD094ABD75E272A97D68E22D25A275D6D0F84ECEB10E
- 8D95E1F68C0E10E1100F55858D78926BA7602CEA9417B358511346E2DE34A3F01DB89DE196E8A76F39660C6A0A28E0E93BF2796DF2040EAFFA549BB8D842EAEF
- 02E57A7DA1F486CDB62AD399123B5857969117CA79A9630B21C1C45913B4FBE4055AF1221E01FD748975DD64622556F187516131DCB5E4EC5CCD40B117C489D7
- 80E323CDB602CFF4C42005850F278C9A2CE05DB0035EB1EC75F837A57CEA9B2B0022050CA0623D56EABCF74E2FC2522F340103C94B175D83B4D5196C9150D6FB
- EC0DFCFF56DD2C611F59E934FB3C3100E8AF474FEED754131E68CA76713D1797A7374F007BC610B625FBE2917941B6DE3E28F8E1751F51E2C3B4CEE7E0523406
- 6CE9EBE1C3BD3E85F5BE7695F8580EA842F66780343CFF578400D4D73AC3D23FF2BE6749481ED471A7CD97304CC6C16FC7EED959A7B56BEF7D3BB8AA5935B5F8
What if we concatenate hashes from 6 to 10 to get password
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
This becomes 640 character password. Very hard to guess and obviously impossible to crack