Re: [L0pht Advisory] MacOS - FWB passwords easily bypassed

From: Bill Genzoli (genzolibat_private)
Date: Tue Nov 03 1998 - 08:33:15 PST

  • Next message: Robert MACDONALD: "Bug (Quirk?) w/Novell BorderManager"

    You need to rethink things here a bit. The only problem is that when the
    Mac's SCSI
    Manager(in the toolbox) goes to mount the drive, the driver insists on
    getting the password to mount it.  LaCie won't actually replace a driver
    unless it can mount the volume first. Even if you try and forcibly replace
    the driver, it wont work.
    
    Bill Genzoli
    Network Admin
    Sacramento County Courts
    genzolbat_private
    -------------
    Original Text
    From: "Space Rogue" <spacerogat_private>, on 10/30/98 4:25 AM:
    To: SMTP@Sys@Sacramento SC[<BUGTRAQat_private>]
    
             Document: L0phT Security Advisory
           URL Origin: http://www.l0pht.com/advisories.html
         Release Date: October 30, 1998 (Special PumpCon Release)
          Application: FWB Hard Disk Toolkit 2.5
             Severity: Users can bypass hard disk driver level passwords
               Author: Space Rogue (spacerogat_private)
     Operating System: Mac OS
    
    
    Description
    -----------
    
    FWB Hard Disk Toolkit 2.5 allows users to password protect hard drive
    volumes. This password has to be entered when the hard disk driver loads
    in order to allow the volume to mount. Failure to enter this password
    prevents the volume from mounting and therefore prevents access to the
    data on the device.
    
    
    Details
    -------
    
    By forcibly replacing the FWB driver with a different driver it is
    possible to access the data on the password protected volume without
    knowing the password.
    
    Most Macintosh hard drive formatting utilities will allow you to replace
    the FWB passworded driver. However they will also make any data on the
    drive unreadable without advanced data recovery software (Norton Volume
    Recover etc.). If the FWB driver is replaced with La Cie Silverlining
    then it is possible to bypass the password and still access the data.
    
    
    Testing
    -------
    
    Our testing procedure utilized a Quadra 610 24/230, Mac OS 8.0, FWB Hard
    Disk Tool Kit 2.5, La Cie Silverlining 5.8.3, and an External 160MB SCSI
    IBM H3171-S2 hard drive.
    
    Our test drive was first low level formatted with FWB and a read/write
    password was assigned. Then about 10MB of various files where copied onto
    it as our test data. The machine was then powered down and rebooted. Upon
    boot up the system prompted us to enter the password. This enabled the
    system to mount the drive.
    
    We then launched Silverlining and updated the driver. Silverlining did
    not complain about doing this except to give us the standard dire
    warnings about possible data loss.  Again we powered down and rebooted.
    This time no password was asked for and the volume mounted successfully
    with all of its data intact.
    
    The previous steps where repeated ten times with no discernible
    differences.
    
    We tried various other hard drive formatting utilities in addition to
    Silverlining such as SCSI Director Pro, Anubis and others. While some of
    these other utilities where able to replace the FWB driver access to the
    data was lost. Silverlining is unique in that attempts to preserve data
    integrity while replacing the driver, other utilities do not take data
    preservation into account.
    
    Solution
    --------
    
    Users should be aware that using a driver level password to protect data
    is not always a guarantee that your data is safe from prying eyes. The
    previous example can be accomplished in under five minutes with a medium
    sized drive and only requires that the malicious user have a bootable
    floppy disk with Silverlining on it. Ten minutes of unsupervised access
    to the target machine is all that is required.
    
    FWB gives users six options when applying a password to a volume; None,
    Read, Read/Write, Encryption Level 1, Encryption Level 2, and Encryption
    Level 3.  Using one of the encryption options would possibly allow for
    greater security. The disadvantage is that using one of the encryption
    options greatly slows down the speed at which your machine can read and
    write data as it does its encryption/decryption on the fly.  (It is not
    the purpose of this advisory to determine if FWBs encryption
    implementation is any better or worse than its password implementation)
    
    Numerous hard drive formatting utilities allow the setting of a password
    similar to FWB. Unfortunately we do not have the time to test them all.
    It should therefore not be assumed that all other driver level passwords
    are secure. This advisory should help illustrate the fact that just
    because a software package or company makes a claim of security does not
    mean that your data is 100 percent secure. Users should take this into
    account when depending on such utilities to protect their data.
    
    
    Notes
    -----
    
    We would like to acknowledge J. Claymore who first mentioned this problem
    some time ago which made this advisory possible.
    
    
    -----------
    For more Macintosh hacking information check out:
    http://www.l0pht.com/~spacerog/index.html
    -----------
    For more L0phT (L - zero - P - H - T) advisories check out:
    http://www.l0pht.com/advisories.html
    -----------
    



    This archive was generated by hypermail 2b30 : Fri Apr 13 2001 - 14:21:56 PDT