hashcat Forum

Hello, my brute force attacks are running much slower than benchmark with the 1700 mode (SHA-512). Is this intended behavior?
example:

hashcat.exe -m 1700 -1 ?l?d -a 3 -w 3 -O --potfile-disable hash.txt abcdefghijk?1?1?1?1?1
...
Speed.#1.........: 47387.2 kH/s (1.66ms) @ Accel:64 Loops:1 Thr:1024 Vec:1
...

hashcat.exe -b -m 1700
...
Speed.#1.........:  272.1 MH/s (45.88ms) @ Accel:64 Loops:32 Thr:1024 Vec:1
...

You've run into a very specific issue that can't be fixed currently. Prefixes in masks cause poor workload, which causes reduced speeds. See here: https://hashcat.net/wiki/doku.php?id=fre...full_speed

Solved, I just used the 1720 mode - sha512(salt:pass) - and got the full speed.

(08-20-2023, 11:27 PM)SeaJoke Wrote: [ -> ]Solved, I just used the 1720 mode - sha512(salt:pass) - and got the full speed.

this shouldnt work, 

plain sha512 and sha512(salt:pass) or sha512(passalt) are different things and switching from mode 1700 to 1720 should lead to an seperator missmatch error

You can use salted variants of hashes to work around the prefix issue and regain speed, which is what I'm assuming was done in this case.

(08-21-2023, 04:29 PM)Chick3nman Wrote: [ -> ]You can use salted variants of hashes to work around the prefix issue and regain speed, which is what I'm assuming was done in this case.

Yep, I just used the known password prefix as a salt

(08-21-2023, 11:47 PM)SeaJoke Wrote: [ -> ]

(08-21-2023, 04:29 PM)Chick3nman Wrote: [ -> ]You can use salted variants of hashes to work around the prefix issue and regain speed, which is what I'm assuming was done in this case.

Yep, I just used the known password prefix as a salt

ah okay, missed that, nice one