Marcus Bakker & Roel van der Jagt Background information Main - - PowerPoint PPT Presentation

marcus bakker amp roel van der jagt background information
SMART_READER_LITE
LIVE PREVIEW

Marcus Bakker & Roel van der Jagt Background information Main - - PowerPoint PPT Presentation

Marcus Bakker & Roel van der Jagt Background information Main question Test approach GPGPU vs CPU Conclusion Discussion Future 2 General computations with GPUs has become available (GPGPU) GPU performances


slide-1
SLIDE 1

Marcus Bakker & Roel van der Jagt

slide-2
SLIDE 2

 Background information  Main question  Test approach  GPGPU vs CPU  Conclusion  Discussion  Future

2

slide-3
SLIDE 3

 General computations with GPUs has

become available (GPGPU)

 GPU performances develop fast  Hashes can be brute forced with enough

power

3

slide-4
SLIDE 4

 What should we (KPMG) advise our clients

regarding password length and complexity now GPU-based password cracking has become reality?

4

slide-5
SLIDE 5

 Length: 6, 8, 10 and 12  Characters: 0, a, a0, aA0, aA0~  5 passwords each  Total: 4*5*5 = 100 passwords  4 tools  4 hashes

  • MD5
  • NTLM
  • DCC
  • Oracle 11g

5

slide-6
SLIDE 6

 Total: 9 tests, 400 hashes, 900 results  Tested for single passwords  Test hardware

  • Intel Core i7 920
  • 2x Nvidia GTX295

6

slide-7
SLIDE 7

7

slide-8
SLIDE 8

8

slide-9
SLIDE 9

9

slide-10
SLIDE 10

10

slide-11
SLIDE 11

 Parallel vs Serial  SIMD

vs SISD

 Limited vs Full instruction set  Disadvantage GPGPU

  • Limited amount of memory available per thread
  • Limited amount of shared memory
  • Off-chip memory access takes a lot of cycles
  • Limited instruction set

11

slide-12
SLIDE 12

12

slide-13
SLIDE 13

13

slide-14
SLIDE 14

14

slide-15
SLIDE 15

 Advised password length

  • aA0~

Nine or more characters

  • aA0

Ten or more characters

  • a0 or A0

Twelve or more characters

 No differences per hash or tool

15

slide-16
SLIDE 16

 Rainbow tables  Dictionary attacks  Crack the hashes left

16

slide-17
SLIDE 17

 GPUs become faster and faster

  • ATI 5970 6.1 billion passwords / second (MD5)
  • 4 times faster

17

slide-18
SLIDE 18

18

slide-19
SLIDE 19

19

slide-20
SLIDE 20

20

slide-21
SLIDE 21

 “A measure for the amount of disorder”  log2(n)  # passwords in keyspace = 2(entropy password)

21

slide-22
SLIDE 22

22

slide-23
SLIDE 23

23