How Do YOU Establish a Secure Computing Environment?

sneakyimp writes "We've seen increasingly creative ways for bad guys to compromise your system like infected pen drives, computers preloaded with malware, mobile phone apps with malware, and a $300 app that can sniff out your encryption keys. On top of these obvious risks, there are lingering questions about the integrity of common operating systems and cloud computing services. Do Windows, OSX, and Linux have security holes? Does Windows supply a backdoor for the U.S. or other governments? Should you really trust your Linux multiverse repository? Do Google and Apple data mine your private mobile phone data for private information? Does Ubuntu's sharing of my data with Amazon compromise my privacy? Can the U.S. Government seize your cloud data without a warrant? Can McAfee or Kaspersky really be trusted? Naturally, the question arises of how to establish and maintain an ironclad workstation or laptop for the purpose of handling sensitive information or doing security research. DARPA has approached the problem by awarding a $21.4M contract to Invincea to create a secure version of Android. What should we do if we don't have $21.4M USD? Is it safe to buy a PC from any manufacturer? Is it even safe to buy individual computer components and assemble one's own machine? Or might the motherboard firmware be compromised? What steps can one take to ensure a truly secure computing environment? Is this even possible? Can anyone recommend a through checklist or suggest best practices?"

Comments

Weigh your options

[Sparticus789]

You have to achieve a personal balance between functionality and security. Security and functionality are inversely proportional. For the average user, having a login password will be enough. If you are storing private data, like tax returns and financial documents, encryption is a good idea. A Truecrypt container with a strong password (16+ characters, upper and lower case letters, numbers, and symbols) will suffice.

If you are of the moderately paranoid group (like me), then FDE, private browsing, and a SSD with TRIM capable motherboard/OS will be enough. If you believe the NSA is watching you, then try taking your meds and refer to the moderately paranoid measures.

There is no security against paranoia

[Peter (Professor) Fo]

1 What are the threats? 2 Why do you care? 3 Expose as little as possible 'publicly' with as few people even knowing you have diamonds in your safe. 4 Have 'CCTV' so you can detect intrusions (and possibly a honeytrap) 5 Assume anyone with $$$ to spend technically will first spend $ on more basic intelligence. 6 [This list goes on and on]

My answer Re:"Secure enough" is "good enough"

[davidwr]

This is about my personal computing, but I would apply the same general principles to other non-critical environments.

What's the worst thing that could happen to my computers? Someone sneaks into my home and installs a hidden camera to catch everything that's on the screen and all keyboard input, AND they somehow install something to log all network traffic and become the man in the middle when they want to.

How likely is this? Unless the feds confuse me with a terrorist and do this with a warrant, it's exceedingly unlikely.

What are some other "high-loss" risks?
* Virus that encrypts my computer and holds it ho$tage
* Virus installs a keylogger that captures an email login, banking credentials, etc. and uses them to impersonate me in a very bad way. "Hi, this is your bank. Your wire transfer to OFFSHOREBANK was processed this morning. This is just a call to remind you of a low-balance fee if sufficient funds are not deposited by the end of the day. Thank you."
* Fire or other calamity that physically destroys my computers, and things a lot more important than my computers.

So here's the big question:

What are the security vulnerabilities I can mitigate cheaper than the "cost" of just not having a network-attached computer at all?

* Fire/theft/physical loss. Mitigated/prevented by backups, casualty insurance, fire extinguishers, etc.
* Theft: Good encryption and good passwords. Pray the thief or his buyer isn't a forensics expert.
* Malware. Mitigated/prevented by backups, low-cost ("$50+tax with $50 mail-in rebate!") security software, "safe-surfing" habits (script-blocking, etc.), 2-way firewalls on the computer and network gateway/router, etc.
* Legal government intrusion: Mitigated/prevented by living in a relatively free country. Cannot be eliminated.
* Illegal/rogue government or ISP intrusion: Mitigated/prevented by living in a relatively free country that can and sometimes will throw individuals responsible in jail. Work on the assumption that this cannot be eliminated.
* WiFi intrusion on my home net: Mitigated by strong encryption and a good pass-phrase and a WiFi Router vendor that I trust.
* WiFi spoofing: Unknown risk.. Other than keeping the password secure and avoiding algorithms that are known to be vulnerable, I don't attempt to mitigate or prevent this.
* Public WiFi hotspots: Compute with care, avoid using them unless absolutely necessary. Prefer my cell phone's "G3/G4" instead of an unsecure or secure-but-untrusted hotspot.
* WiFi- and Bluetooth-based attacks: Turn off WiFi when not in use. Don't allow connections in or out without my permission.
* Backup failure: Test backups. Have multiple backups in multiple formats from multiple points in time.
* File format obsolescence: Have really important stuff in formats that will likely outlive the usefulness of the data. .TXT, TAB- and comman-delimited simple spreadsheets, .GIF and .JPEG images, and some versions of PostScript and PDF files are among the many formats that will likely be easily readable 10 or 20 years from now assuming the media is still readable or that the file has been copied to new media before it became unreadable. Human-readable paper printouts, photographic slides, and photographic negatives are also pretty much immune from becoming technologically obsolete in my lifetime, but they require large amounts of space and a certain amount of care. Paper and especially film also decays over a 10-100 year time frame.

Bottom line:
* If I lose everything I have on my computer, it won't drive me to suicide.
* The very important stuff is backed up in multiple places including offsite and in multiple formats.
* The medium-important stuff is backed up.
* If I can prevent a large amount of likely damage at a low cost, I'll do it.
* If I can't afford to lose it, I can't afford to NOT insure against loss.

Re:linux

[jc42]

Oh right linux makes you immune from things like buffer overflows or user assisted attacks.

Nice strawman there. ;-) Of course it doesn't. But its open-source nature greatly increases the chances that 1) backdoors will be discovered by interested geeks and removed, and 2) people other than employees of the vendor will be able to fix problems quickly.

I ran across a case of this a while back, when I got a message from one of djb's team telling me how to exploit a security hole in a program used by one of my web sites. I tried it, the exploit succeeded. I opened up the code, found the problem (and a couple more related to it), fixed them, verified that the exploit no longer worked, and sent a letter thanking the guy for the info.

With closed-source software, I couldn't have done any of this. I'd have had to report it to the code's owners, and try to talk them into fixing it. If they decided to fix it (which isn't guaranteed), it would typically take months, during which time my site would have been vulnerable.

I also sent a description of the exploit, along with my patches, back to the code's author, who sent me a letter of thanks, and a day later I saw the message he'd sent to all his known users announcing the "security upgrade" that fixed the problem. The total time for this was under 3 days, which is orders of magnitude faster than most security fixes from commercial closed-source vendors.

Yeah, unix/linux and other open-source systems are vulnerable. But they're so much better at fixing problems that you'd have to be rather gullible to depend on software that doesn't supply this sort of response capability.

(And yes, I understand that most of the buying public is rather gullible. The commercial world depends on that, y'know. I also understand the argument that most people wouldn't know what to do with source code, but I consider this argument bogus. It means that you deny access to people like me, who are able to understand the code and fix it. I've done this many times during my career. You should be encouraging people like me, by making sure we can get at the code to your software. ;-)