Microsoft Outlook PST Exposure

Secure Target Network (Security Advisory August 31, 2003)

Topic: Microsoft Outlook PST Exposure
Discovery Date: August 28, 2003
Original Advisory
External: Zone-h, Security Tracker, openwall, Full-Disclosure
Affected applications and platforms:
All versions of Outlook on any Windows platform

Introduction:
everyone work with .pst files, storing and managing his/her Outlook Data transparently under Microsoft Outlook. A default folder takes care of these data files at:
%windrive%\Documents and Settings\User Profile\Local Settings\Application Data\Microsoft\outlook
And all of your data may encrypt and maintain as outlook.pst (or archive.pst when you just archive your old data).
When you add something to your outlook items (appointments & meetings, tasks, notes, …), your data file probably increases in size but when you delete some items (any size, large or small piece of data), the data do lost from your eyes but usually, does not erase from .pst files.

Exploit:
As you can probably see, this may effect in a wide range of exposure attacks; no escalation of privileges or any other system compromise directly happen. So, anybody with physical access to your computer would be the reader of your Outlook Items (any task, appointment and …) and any private information there.
By the way, this may lead to a worth situation, when you just restore a backed up copy of these .pst files and try to recover your lost data, but there is something different in backups, because you didn’t copy a refreshed one.

Workaround:
the easiest way to work around this vulnerability is physical security countermeasures but for your backups, try to “compact” items before backing up:
1. Fileàfolderàproperties of “your desired folder with data files”àGeneral tabàAdvancedàCompact Now
2. FileàData File ManagementàsettingsàCompact Now

Tested on:
Outlook 2000 SP3 (9.0.0.6627) on Windows 2000 SP4
Outlook 2002 (10.2627.2625) on Windows XP Professional SP1

Feedback:
Kaveh Mofidi ( Admin (at) SecureTarget [dot] net )
SECURE TARGET, Cyber Security Research


Affected applications and platforms:
All versions of Outlook on any Windows platform

Introduction:
everyone work with .pst files, storing and managing his/her Outlook Data transparently under Microsoft Outlook. A default folder takes care of these data files at:
%windrive%\Documents and Settings\User Profile\Local Settings\Application Data\Microsoft\outlook
And all of your data may encrypt and maintain as outlook.pst (or archive.pst when you just archive your old data).
When you add something to your outlook items (appointments & meetings, tasks, notes, …), your data file probably increases in size but when you delete some items (any size, large or small piece of data), the data do lost from your eyes but usually, does not erase from .pst files.

Exploit:
As you can probably see, this may effect in a wide range of exposure attacks; no escalation of privileges or any other system compromise directly happen. So, anybody with physical access to your computer would be the reader of your Outlook Items (any task, appointment and …) and any private information there.
By the way, this may lead to a worth situation, when you just restore a backed up copy of these .pst files and try to recover your lost data, but there is something different in backups, because you didn’t copy a refreshed one.

Workaround:
the easiest way to work around this vulnerability is physical security countermeasures but for your backups, try to “compact” items before backing up:
1. Fileàfolderàproperties of “your desired folder with data files”àGeneral tabàAdvancedàCompact Now
2. FileàData File ManagementàsettingsàCompact Now

Tested on:
Outlook 2000 SP3 (9.0.0.6627) on Windows 2000 SP4
Outlook 2002 (10.2627.2625) on Windows XP Professional SP1

Feedback:
Kaveh Mofidi ( Admin (at) SecureTarget [dot] net )
SECURE TARGET, Cyber Security Research

By Kaveh Mofidi

I find simple solutions for huge and complicated problems. I believe information security and computers in general are fun to deal with, but our problems are way bigger than securing information. The real deal is to find solution for unlimited clean energy, drinkable water, mitigate root cause of hunger, war, and injustice...We need to keep our planet livable, that is our real problem on the Earth! Contact me with any question or comment: kaveh@securetarget.net

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