Wrong NSRange calculations in [DBMatcher sequenceMatch]

[tagyro]

Steps to reproduce:

• run demo app (after removing the code from AppDelegate)

• enter text in password field, select all, delete, enter text

• eventually the app will crash:

  *** Terminating app due to uncaught exception 'NSRangeException', reason: '-[__NSCFString substringWithRange:]: Range {11, 1} out of bounds; string length 11'
  *** First throw call stack:
  CoreFoundation 0x0000000101944bbd -[__NSCFString substringWithRange:] + 125
  Zxcvbn 0x0000000100009788 __26-[DBMatcher sequenceMatch]_block_invoke + 1816

[leah]

Hi @tagyro,

I'm unable to reproduce this issue. Are you entering any special characters? Are you using the simulator or a device?

The substringWithRange method is used all over the place in DBMatcher and DBScorer. Any clue where this error is occurring?

Thanks!

[tagyro]

Hi @leah
I've been able to reproduce the crash consistently by following these steps:

• run the demo (in the simulator or device, I've been able to reproduce it on both)
• enter text in the password field
• select text and delete or, without deleting, enter a new character
• eventually the app will crash
  The crash log suggest the problem is in the sequenceMatch method in the DBMatcher.m file.

Note: if I just clone the repo and run the demo, the app crashes on launch because of the passwords array test in the AppDelegate.m. I commented out those lines to be able to run the app!
I've uploaded a video on Mega: https://mega.co.nz/#!BAtnTBIS!NmSiAC4XsMM3Z67XLr9VWEtEniMdbPrC_GOyYZ9dkCA