Re: [Full-disclosure] [IVIZ-08-001] Microsoft Bitlocker Plain Text Password Disclosure

[Juha-Matti Laurio <juha-matti.laurio@xxxxxxxx>]

Any advisories, CVE available?

The following non-English advisory has been released:
https://www.cert.dk/nyheder/nyheder.shtml?08-08-26-11-14-00

Juha-Matti

iViZ Security Advisories [advisories@xxxxxxxxxxxxxxxxxxxxxxx] wrote: 
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> - -----------------------------------------------------------------------
> [ iViZ Security Advisory 08-001                            25/08/2008 ]
> - -----------------------------------------------------------------------
> iViZ Techno Solutions Pvt. Ltd.
>                                             http://www.ivizsecurity.com
> - -----------------------------------------------------------------------
> 
> * Title:     Microsoft Bitlocker Plain Text Password Disclosure
> * Date:      25/08/2008
> * Software:  Microsoft Bitlocker
> 
> - --[ Synopsis:
> 
>     Bitlocker is the disk encryption feature introduced in Microsoft
>     Vista. It has the capability to authentify users in several way,
>     including with a password (PIN), when configured to work with the
>     TPM chip.
> 
>     The password checking routine of Microsoft Bitlocker fails to
>     sanitize the BIOS keyboard buffer after reading passwords, resulting
>     in plain text password leakage to unprivileged local users.
> 
> - --[ Affected Software:
> 
>   * Microsoft Bitlocker/Vista (SP0)
> 
> - --[ Non Affected Software:
> 
>   * Microsoft Bitlocker/Vista (SP1)
> 
> - --[ Technical description:
> 
>     Bitlocker's pre-boot authentication routines use the BIOS API to
>     read user input via the keyboard. The BIOS internally copies the
>     keystrokes in a RAM structure called the BIOS Keyboard buffer
>     inside the BIOS Data Area. This buffer is not flushed after use,
>     resulting in potential plain text password leakage once the OS
>     is fully booted, assuming the attacker can read the password at
>     physical memory location 0x40:0x1e.
> 
> 
> - --[ Impact:
> 
>     Plain text password disclosure. Local guest access is required,
>     but no physical access to the machine.
> 
> - --[ Full Technical Whitepaper
> 
>     http://www.ivizsecurity.com/research/preboot/preboot_whitepaper.pdf
> 
> - --[ Vendor response:
> 
>   * Microsoft Bitlocker Team has aknowledged the vulnerability.
>     This vulnerability is fixed in Microsoft Windows Vista (SP1)
> 
> - --[ Credits:
> 
>     This vulnerability was discovered by Security Researcher
>     Jonathan Brossard from iViZ Techno Solutions Pvt. Ltd.
> 
> - --[ Disclosure timeline:
> 
>   * First private disclosure to vendor on May 27th 2008
>   * First vendor reply on May 30th 2008
>   * First Public disclosure at Defcon 16 on August 10th 2008
> 
> - --[ Reference:
> 
>     http://www.ivizsecurity.com/security-advisory.html
> 
> 
> 
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