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		08-20-2023, 09:21 PM 
(This post was last modified: 08-20-2023, 09:22 PM by SeaJoke.)
		
	 
	
		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
...
	
	
	
	
	
 
 
	
	
	
		
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		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
	 
 
	
	
	
		
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		Solved, I just used the 1720 mode - sha512(salt:pass) - and got the full speed.
	
	
	
	
	
 
 
	
	
	
		
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		 (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(pass

alt) are different things and switching from mode 1700 to 1720 should lead to an seperator missmatch error
	
 
	
	
	
	
 
 
	
	
	
		
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		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.
	
	
	
	
	
 
 
	
	
	
		
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		 (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
	
 
	
	
	
	
 
 
	
	
	
		
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		 (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