RE: [Full-Disclosure] harddisk encryption

Glenn_Everhart_at_bankone.com
Date: 02/15/05

  • Next message: CorryL: "ASPjar Guestbook login.asp not official patch" 
    Date: Tue, 15 Feb 2005 11:39:42 -0500
To: <ledeve@gmx.net>, <full-disclosure@lists.netsys.com>

    Comments on hard drive encryptors:

    1. If the encryptor encrypts your boot disk, it has to be involved early in the
    boot process and may be broken by anything that changes the system boot sequence.
    On the whole such a product would likely need two different drivers, one of which
    would change BIOS behavior, and the other of which would change runtime
    OS behavior, and they must be in synch with one another.

      This is fine until you decide to change operating systems, at which point the boot
    may change and make your old data suddenly disappear. Things on the other hand are
    easier if the encrypting disk product only encrypts data devices (including virtual
    disks) since only one driver need be used.

    2. In the event of disk crash or emergency, unless a tool is provided to allow you
    to access the encrypted disk from somewhere else, anything which causes an OS to
    become non bootable may be unfixable. You would not normally want such a tool online,
    but when you need it, you REALLY need it.

    3. If a product says it can encrypt local disks but not network ones, you may want
    to know what exactly is going on. Something that exists just above the hardware control
    layer would be expected to produce disk structures which would share across networks
    normally when the encryption keys had been entered. If some OS layers cannot see
    the disk as a normal disk, some programs may also be affected.

    4. An interesting question to ask of such a package is whether the data in any
    disk block is a cipher depending only on a fixed key and the original data. If so,
    and the same key is used for every block, there are attacks which can be used
    to compromise such a system without having to decrypt it all. If on the other hand
    something else is an input, you need to know what else is used and how it is
    used and how key scheduling is done, to make any estimate of how strong the
    cipher really is.

    (Now mind: most of the attackers will not be cryptanalysts, and thus even a
    cipher that cryptanalysts laugh at has value in discouraging curious system
    admins, PHBs, or others who may be able to get privileged access to a box but
    lack knowledge or time to crack the cipher. A vendor or author who acknowledges
    this is not vending snake oil...just admitting limitations of some methods.)

    The Ultimaco literature suggests that many users may have different passwords to
    access a computer disk protected by its package. If I were buying it in bulk I
    would certainly want to know more about how the key management is done to allow
    this.

    Over the long term, leakage of some sensitive data onto swap files is often
    a very minor exposure compared to what is protected with an encrypted virtual
    disk, and its continued function generally is easier to maintain than anything
    that has to deal with both boot and runtime OS environments...and not much
    different in training requirements. Remember too there are in Windows some
    registry controls that allow the swap file to be wiped on shutdown.

    -----Original Message-----
    From: full-disclosure-bounces@lists.netsys.com
    [mailto:full-disclosure-bounces@lists.netsys.com]On Behalf Of Lentila de
    Vultur
    Sent: Tuesday, February 15, 2005 10:05 AM
    To: full-disclosure@lists.netsys.com
    Subject: [Full-Disclosure] harddisk encryption

    hi,

    sorry for my late answer and for breaking the thread. below you can find the
    original post:

    <>
    i'm evaluating a software that performs harddisk encryption for deploying in
    my company. the software in question is utimaco safeguard easy v4.10
    (www.utimaco.com) running on w2k.

    i am interested in communitty's oppinion about this product. has anyone
    performed a detailed analysis of it? i googled around but i couldn't find
    much information, except that the version 3.20 sr1 has earned an eal3
    certification from the german federal agency for it security.
    </>

    thank you for all your answers and suggestions on and off the list.

    what i like at safeguard easy are the possibility to encrypt full harddisks,
    not only files or partitions, and the boot authentication. Frank Knobbe
    suggested encryption plus hard disk from pc guardian - I asked for an
    evaluation copy. google suggested also drive crypt plus pack -
    www.securstar.com.

    imho, the main disadvantage of pgpdisk and alike compared with
    full-encryption tools is that valuable data can remain unencrypted in the
    swap file or in temporary files outside the container. When using full
    harddisk encryption tools no extra user interaction is required, everything
    is done transparently. there is no need for user training. 

    -- 
this e-mail is certified content-free.
Lassen Sie Ihren Gedanken freien Lauf... z.B. per FreeSMS
GMX bietet bis zu 100 FreeSMS/Monat: http://www.gmx.net/de/go/mail
_______________________________________________
Full-Disclosure - We believe in it.
Charter: http://lists.netsys.com/full-disclosure-charter.html
**********************************************************************
This transmission may contain information that is privileged, confidential and/or exempt from disclosure under applicable law. If you are not the intended recipient, you are hereby notified that any disclosure, copying, distribution, or use of the information contained herein (including any reliance thereon) is STRICTLY PROHIBITED. If you received this transmission in error, please immediately contact the sender and destroy the material in its entirety, whether in electronic or hard copy format. Thank you
**********************************************************************
_______________________________________________
Full-Disclosure - We believe in it.
Charter: http://lists.netsys.com/full-disclosure-charter.html
  • Next message: CorryL: "ASPjar Guestbook login.asp not official patch"

    Relevant Pages

    • Re: New laptop - resize win partition?
      ... Torfinn> Only one small snag - the disk is encrypted (with ... which means that I'll have to boot ... having both the encrypted Windows volume and an unencrypted FreeBSD ... talk the client CISO into letting me install the disk encryption ...
      (comp.unix.bsd.freebsd.misc)
    • Attack Scenarios against PGPs Whole Disk Encryption (WDE)
      ... Attack Scenarios against PGP's Whole Disk Encryption ... PGP's Whole Disk Encryption for Microsoft Windows encrypts all the ... As long as standard PC hardware and BIOS is used, the boot code of the disk ...
      (comp.security.pgp.tech)
    • Re: win 2k file encryption
      ... >Installed new disk in computer and put windows 2k pro on it. ... I thought that administrator was default recovery agent. ... >The other HD is dead and I can't boot from it any more. ... you enabled the encryption, so you need to understand the next line. ...
      (sci.crypt)
    • RE: [Full-Disclosure] harddisk encryption
      ... > boot process and may be broken by anything that changes the system boot ... In the event of disk crash or emergency, unless a tool is provided to ... > i'm evaluating a software that performs harddisk encryption for deploying ...
      (Full-Disclosure)
    • Re: Booting a GELI encrypted hard disk
      ... a GELI encrypted hard disk, ... someone needs your data, he can dump encrypted partition, trojan your ... My knowledge of encryption at the storage level is limited at best... ... that when rebooted, does not boot (thumb drive can be removed once ...
      (freebsd-questions)
    Loading