I know this was asked for previous releases. Has anything changed for 16.04? The official documentation hasn't been updated for a while.   If FDE after installation is not possible, what about encrypt /home (for all users, not just one). Any outstanding bug preventing it from working properly? I have hit so many bugs in 16.04.
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I'm running 13.10 Saucy. If I didn't enable disk encryption during installation, is there any way to enable it post facto?    I found , which says that encryption has to happen at install time, but it's also referring to Fedora. I can easily boot into a live disk if there's any way to do it from there.
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I've been a Windows power user/administrator and professional tech for years, I just made the decision to go Linux, and wow, what a difference.     Is there any decently easy way to encrypt external volumes (i.e. USB keys, external hard drives, memory sticks, etc.) that works under Ubuntu 14.04?
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Does the  file format use a serious encryption (such as )?  Will it take unfeasibly long to brute force a password?  If not, what tools do you suggest that do so automatically?
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I am lazy at home and use password authentication for my home machines. I am ready to move to key based authentication. There are many options on the web on how to do this, including catting then sshing the key over, scping the key over directly, etc.  I am looking for the easiest and recommended way to copy a key over, hopefully there is a convenience wrapper somewhere in the Ubuntu ssh package?  I'm already aware on .
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Any questions relating to status updates, or asking if anything is going to be patched for these vulnerabilities should be closed as duplicates of this question.    are in the news right now and sound pretty severe. I don't see any security updates from Ubuntu that cover these vulnerabilities.  What is Ubuntu doing about these vulnerabilities, and what should Ubuntu users be doing?  These are CVE-2017-5753, CVE-2017-5715 and CVE-2017-5754.
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Clicking on  doesn't connect me with the meta S.Ex.SE site.  EDIT: For some entry points, . Observation courtesy Gilles.  I consider it a pity that the devs have not paid attention to this issue nor have indicated that they noted the problem. While HTTPS is not yet official on this network, I refrain from using unencrypted connections. I can't participate in metas, oh well.  EDIT #2 (2015-11-07) - with the switch to CloudFlare SSL the problem looks finally resolved.  EDIT #3 (2015-11-17) - still getting 403 Forbidden from CloudFlare. D'rats!..  EDIT #4 (2016-01-11) - We're still there. It's 2016 already... Starting a bounty.
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Is there any way you could revive Guest Sessions in a future LTS distro?  Guest sessions are good security - they give me just enough power to do what I need to do on a daily basis without risking my system. In short, Guest sessions save me from myself.  I had upgraded from 16.04 to 18.04, gotten a problem I couldn't fix and was all to happy to wipe and rebuild my hard drive and return to 16.04.  I can't be the only one who feels this way.
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I have an encryption/copy protection question.  I'm writing an application for a company that uses a dongle.  Please don't tell me that software protection is useless, or that I should just let it fly free into the air, or that any time I spend doing this is a waste; this isn't a philosophical question about the validity of software protection, more like a how-to.  As I understand it, the first step in cracking a dongle-protected piece of software is to remove all the calls to the dongle from the code (ie, patch the executable).  Also as I understand it, I can create 'strong names' in .NET in order to protect the application and the assembly, as explained .  Is strong naming enough to ensure that my application can't be easily patched?  Or do I need to use some sort of encryption library?  If I need to use a library, which one, or where can I get information about setting this up?  The next step, of course, is to put important algorithms on the dongle.  I realize that these are just speed bumps to the dedicated cracker, but as our market share grows, the speed bump will help us get to the point where the sting of piracy is not so keenly felt (I hope).  Thanks!
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I love encfs as it provides file-based encrypting which is quite useful when it comes to cloud storage. But it looks like that especially for this use case, . I'm aware that  but how to deal with it in the meantime? Are there any alternatives that integrate well in ubuntu?  Edit: The security issue I mostly refer to is . It is still present in version 1.8 and makes your files vulnerable if someone get's multiple versions of your encrypted files. If one is worried about services like Dropbox are not that thrustworthy and encrypts folders uploaded into the cloud because of that, the opportunity that the attacker (the service) gets more than one copy of the cyphertext is absolutely given.
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I encountered a simple function that even FHE cannot solve. Here's it:  int f(a,b,c,d){    if(a+b&gt;c+d) return a+c;       else return b+d; }   Since FHE is not order-preserving, one can't figure out whether a+b>c+d without the decryption key. That means even if practical FHE was implemented, f(a,b,c,d) cannot be computed in the Cloud independantly and securely. Not to mention linear regression, or more complex functions.  So I wonder with such an obvious limitation, why is FHE called "the holy grail of cryptography"?
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Mountain Lion allows one to encrypt any disk by right-clicking on the disk in the Finder and selecting Encrypt  from the contextual menu.  Is there anyway to check on the progress of this encryption process?
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Is there some chance to know how a binary was built, under Linux? (and or other Unix)  Compiler, version, time, flags etc...  I looked at readelf and couldn't find much, but there might be other ways at analyzing the binary code/section etc...  Anything you know how to extract?
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I have read that there is a bug in SSL called heart bleed bug. Has Ubuntu 14.04 shipped along with this bug or has it been resolved in this release?
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What tool or technique do you use to prevent brute force attacks against your ssh port. I noticed in my Security logs, that I have millions of attempts to login as various users through ssh.  This is on a FreeBSD box, but I imagine it would be applicable anywhere.
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I am looking to encrypt some data using  in  using a specific key and  value. Are there any good function libraries or COM components that would be good to use?  I looked at ; it allows a passphrase only, and won't allow setting specific key and IV values.
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I found this page with some examples:   I'm wondering which one to use. Any suggestions? I'm using other packages too so whichever is less likely to interfere with them is better for me.
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I have found a guide for that but doesn't sure if it will work or it is safe to use. The guide:  I am asking if is these introductions safe and will work? If not, is there any other solutions for that? I am using Ubuntu 20.04 LTS Thank you.