why Hashcat v6.2.5 is slower than v5.1.0

[v71221]

I managed to run Hashcat v6.2.5 on Linux.
For simplicity, I run Ubuntu directly from a USB stick without installing it on a hard disk.
I chose Ubuntu because it is recommended by Hashcat team.
https://hashcat.net/forum/thread-6620-po...l#pid35318
https://hashcat.net/forum/thread-6661-po...l#pid40381
https://hashcat.net/forum/thread-7639-po...l#pid41025

Download an Ubuntu image (why version 16.04 ? Because prerequisite, see below)
https://releases.ubuntu.com/16.04.7/ubun...-amd64.iso

Create a bootable USB flash drive
https://ubuntu.com/tutorials/create-a-us...on-windows

Boot from USB flash drive and choose
Try Ubuntu without installing

Code:

ubuntu@ubuntu:~$ uname -r
4.15.0-112-generic

ubuntu@ubuntu:~$ uname -a
Linux ubuntu 4.15.0-112-generic #113~16.04.1-Ubuntu SMP Fri Jul 10 04:37:08 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

Then you need to download Intel CPU Runtime for OpenCL Applications 18.1 for Linux OS (64bit only).

See here
https://www.intel.com/content/www/us/en/...ivers.html

Or use direct links
*ttp://registrationcenter-download.intel.com/akdlm/irc_nas/vcp/15532/l_opencl_p_18.1.0.015.tgz
or
*ttps://registrationcenter-download.intel.com/akdlm/irc_nas/vcp/15532/l_opencl_p_18.1.0.015.tgz

Supported operating systems for this release are:
- CentOS 7 (Intel(R) 64)
- Red Hat Enterprise Linux 7 (Intel(R) 64)
- SUSE Linux Enterprise Server 12 (Intel(R) 64)
- Ubuntu 16.04 (Intel(R) 64)

Then
sudo add-apt-repository universe
sudo apt update
sudo apt install lsb-core  (prerequisite for install.sh)
sudo apt install p7zip  (needed for unpacking 7z-archives)

Unpack tgz-file
tar -xzf l_opencl_p_18.1.0.015.tgz

Run ./install.sh

Download https://hashcat.net/files/hashcat-6.2.5.7z

Unpack 7z-file
p7zip -d hashcat-6.2.5.7z

I got a working hashcat v6.2.5

Code:

ubuntu@ubuntu:~/hashcat-6.2.5$ ./hashcat.bin -I

hashcat (v6.2.5) starting in backend information mode

OpenCL Info:
============

OpenCL Platform ID #1
  Vendor..: Intel(R) Corporation
  Name....: Intel(R) CPU Runtime for OpenCL(TM) Applications
  Version.: OpenCL 2.1 LINUX

  Backend Device ID #1
    Type...........: CPU
    Vendor.ID......: 8
    Vendor.........: Intel(R) Corporation
    Name...........: Intel(R) Celeron(R) CPU 1005M @ 1.90GHz
    Version........: OpenCL 2.1 (Build 0)
    Processor(s)...: 2
    Clock..........: 1900
    Memory.Total...: 15926 MB (limited to 1990 MB allocatable in one block)
    Memory.Free....: 7931 MB
    OpenCL.Version.: OpenCL C 2.0
    Driver.Version.: 18.1.0.0920


ubuntu@ubuntu:~/hashcat-6.2.5$ ./hashcat.bin  -a 3  -m 22000  "WPA*01*ca5396d611cf330aebefd48ebbfb0e63*020000000001*020000000020*61703031***"  "12345678"

hashcat (v6.2.5) starting

OpenCL API (OpenCL 2.1 LINUX) - Platform #1 [Intel(R) Corporation]
==================================================================
* Device #1: Intel(R) Celeron(R) CPU 1005M @ 1.90GHz, 7931/15926 MB (1990 MB allocatable), 2MCU

Minimum password length supported by kernel: 8
Maximum password length supported by kernel: 63

Hashes: 1 digests; 1 unique digests, 1 unique salts
Bitmaps: 16 bits, 65536 entries, 0x0000ffff mask, 262144 bytes, 5/13 rotates

Optimizers applied:
* Zero-Byte
* Single-Hash
* Single-Salt
* Brute-Force
* Slow-Hash-SIMD-LOOP

Watchdog: Temperature abort trigger set to 90c

Host memory required for this attack: 0 MB

The wordlist or mask that you are using is too small.
This means that hashcat cannot use the full parallel power of your device(s).
Unless you supply more work, your cracking speed will drop.
For tips on supplying more work, see: https://hashcat.net/faq/morework

Approaching final keyspace - workload adjusted.         

ca5396d611cf330aebefd48ebbfb0e63:020000000001:020000000020:ap01:12345678
                                                         
Session..........: hashcat
Status...........: Cracked
Hash.Mode........: 22000 (WPA-PBKDF2-PMKID+EAPOL)
Hash.Target......: ca5396d611cf330aebefd48ebbfb0e63:020000000001:02000...0:ap01
Time.Started.....: Sun Mar 20 15:24:47 2022 (0 secs)
Time.Estimated...: Sun Mar 20 15:24:47 2022 (0 secs)
Kernel.Feature...: Pure Kernel
Guess.Mask.......: 12345678 [8]
Guess.Queue......: 1/1 (100.00%)
Speed.#1.........:      161 H/s (0.34ms) @ Accel:128 Loops:256 Thr:1 Vec:4
Recovered........: 1/1 (100.00%) Digests
Progress.........: 1/1 (100.00%)
Rejected.........: 0/1 (0.00%)
Restore.Point....: 0/1 (0.00%)
Restore.Sub.#1...: Salt:0 Amplifier:0-1 Iteration:0-1
Candidate.Engine.: Device Generator
Candidates.#1....: 12345678 -> 12345678
Hardware.Mon.#1..: Temp: 51c Util: 55%

Started: Sun Mar 20 15:24:40 2022
Stopped: Sun Mar 20 15:24:49 2022

Some info was helpful for me here
https://www.alexanderjsingleton.com/info...ntu-18-04/