Solved

Auto-Lock a file based on date

Posted on 2009-04-14
8
858 Views
Last Modified: 2013-11-15
I have a client that sends files to organizations with time sensitive data.  She doesn't want folks to be able to open the file after a certain date that she specifies.  These files are simple Excel files, but could be PDF, DOC, or even ZIP files.  She wants a program she can run, select a file she will send, and specify in the application that the selected file should lock itself so it can't be opened in 10 days.  Then she wants to send that file to these organizations.
0
Comment
Question by:hazenweber
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 4
  • 3
8 Comments
 
LVL 33

Accepted Solution

by:
Dave Howe earned 250 total points
ID: 24143466
this has been tried several times, but isn't really practical.

the key criteria are that the file must be (and remain) locked, must be viewable only (so not printed, copyable or screenshottable) and must be dependent on a trusted clock (i.e. one on the internet or other external source, not the local pc, where the user could just set the clock back)

the last company to try and field a solution in this space was "disappearing, inc" which did time-limited emails - I think they had been officially "in the field" for three days when the first posted crack allowed offline copy of their "self deleting" emails, so they are moving more to an integrated DLP solution and have changed the company name to reflect this.

it is believed that it would be possible, by combining the trusted rendering path (used to try and discourage copying of movies) and Trusted Computing (where the cpu itself acts in support of the vendors instead of the owner of the machine) to prevent rendered documents being captured in digital form - which would leave really only screen photography (webcam and OCR could recover documents with a high degree of reliability) - but there are obviously privacy and security issues with handing over fundamental control over your machine to a third party (microsoft, for example) particularly if it could be in their commercial interests to abuse that, and for a number of potential customers (banks, for example) that would violate a number of laws. In any case, if such a platform were made the only available purchase choice from now, you would still expect a proportion of your customer base to be using "old" technology five years from now, so in the near term it isn't an option.
0
 
LVL 2

Expert Comment

by:SadiDev
ID: 24193120
Till now it is not possible to apply any individual file (by using generic software).
But you can use/create any container/host (customized) program that will contain the file (encrypted) and make the file viewable for certain time, but never write file to the disk and prohibit any copy/snap/print. The problem is, why other organization blindly trust an executable file (which they can not control)?
0
 
LVL 33

Expert Comment

by:Dave Howe
ID: 24197741
sadidev: the problem there is ensuring that the clock is accurate - otherwise, you just set the clock back into the "valid" period and the file opens...
0
SuperAntiSpyware Licenses Discounted by 25% !

Exclusive offer to Experts Exchange Members!
Buy SuperAntiSpyware License(s) from us and save 25% on the regular purchase price.
- Includes Full SuperAntiSpyware Vendor Support Entitlements
- Your Subscription does not begin until you activate your license
- Buy for your friends

 
LVL 2

Assisted Solution

by:SadiDev
SadiDev earned 250 total points
ID: 24200363
Yes, there is depend on trusted clock. Only internet/server clock can be trusted not the local computer. Sorry I did not mentioned it.
0
 
LVL 33

Expert Comment

by:Dave Howe
ID: 24202336
not even an internet clock can really be trusted - you need to run your own server, at which point you are probably better off just doing what invisible inc did - host the content on the server and allow it to be viewable though an applet.
0
 
LVL 2

Expert Comment

by:SadiDev
ID: 24202424
Actually nothing can be 100% secure. Trusted server can be spoofed. Of course there are always better way to secure something. We can make something, that might be harder to break. Anyway thank you (DaveHowe) for pointing to it more specifically.
0
 
LVL 33

Expert Comment

by:Dave Howe
ID: 24203099
trusted server can't be spoofed, provided you use PKI - but as I say, if you have to run a server anyway, host the content locally to the server, access it though a java applet or flash applet, and all the client has to do is pass a couple of parameters (document id and auth string) to read the document up to the point the server is told to no longer accept that auth string.

anything else is asking for the local applet to be hacked to not bother checking the date.
0

Featured Post

Complete VMware vSphere® ESX(i) & Hyper-V Backup

Capture your entire system, including the host, with patented disk imaging integrated with VMware VADP / Microsoft VSS and RCT. RTOs is as low as 15 seconds with Acronis Active Restore™. You can enjoy unlimited P2V/V2V migrations from any source (even from a different hypervisor)

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Ransomware is a malware that is again in the list of security  concerns. Not only for companies, but also for Government security and  even at personal use. IT departments should be aware and have the right  knowledge to how to fight it.
This article demonstrates probably the easiest way to configure domain-wide tier isolation within Active Directory. If you do not know tier isolation read https://technet.microsoft.com/en-us/windows-server-docs/security/securing-privileged-access/s…
This video demonstrates how to use each tool, their shortcuts, where and when to use them, and how to use the keyboard to improve workflow.
This is used to tweak the memory usage for your computer, it is used for servers more so than workstations but just be careful editing registry settings as it may cause irreversible results. I hold no responsibility for anything you do to the regist…

737 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question