Do not use default options for the scrypt utility and keepass2!

Here is example with more secure options: 

$ sudo apt-get install scrypt
$ scrypt enc -M 1073741824 -t 200 secret.txt encrypted.scrypt

If you have several GB of free memory you can increase the memory usage several times.

My tests confirm that the "-t" parameter is not working correctly - it takes less than 200 seconds to derive the key from your password.

Archiving private keys - TLDR version

Learn more about key stretching.

Keepass2 have the option to specify how slow should be the KDF. Click on "1 second" and then add one zero at the end of the number (10 seconds). This will slow down the opening of the database. However, it will also slow down the saving.

After I tried to open the database made by Keepass2 with KeepassX I noticed that KeepassX is opening the database much faster than Keepass2 (it takes part of the second compared to 10 seconds with KeePass2). This means that you get false sense of security when your KDF hardness is set to 10 seconds (5701900 on my computer) with Keepass2, because with the most efficient algorithm it takes less than a second (I don't know how efficient is the algorithm used by KeepassX, but it's obviously very efficient compared to KeePass2).

How to encrypt your secretes with the scrypt utility on Ubuntu, print them on paper and then read them again.

Comments

Post a Comment

Popular posts from this blog

Do not use (only) flash memory (SSD drives, hardware wallets, USB flash drives) for your precious private keys!

Image
Flash memory is not a reliable medium for archives. Especially when there is no regular power. I have personal experience with usb flash drive not powered for weeks - one file became corrupted . (Read more here: Archiving private keys - TLDR version. ) You should always back up on paper and other mediums. Flash memory is prone to failure if it is not powered for weeks or more and if there are ionizing radiation When you write your precious private keys you should use technologies like Parchive and ZFS . And make several copies of your files. It's OK if you use your USB flash drive for another backup, but don't rely on it! Always back up on DVDs (even small files!), paper and online (after encryption with CPU and RAM intensive key derivative function like scrypt). Here is example of using the scrypt utility: $ sudo apt-get install scrypt $ scrypt enc -M 1073741824 -t 200 secret.txt encrypted.scrypt Do not use default values of "-M" and "-t", they
Read more

Archiving private keys - TLDR version

0. Make multiple encrypted copies. On DVDs (they are better than CDs and Blu-Ray discs; DVD+R are better than DVD-R), paper, cloud services like DropBox, OneDrive, Google Drive, e-mail it to yourself and to your friends, use P2P storage services like MaidSafe, Storj and Sia , etc. 1. Use proper font when printing PGP encrypted keys on paper. 2. Flash memory (SSD, USB flash drives, hardware wallets) is less reliable when not powered regularly (i.e. every week). 3. Use error correction methods like Parchive and ZFS. 4. Print on paper or store on digital media only encrypted data. 5. Your encryption software should use CPU/RAM-intensive KDF (i.e. scrypt with secure options - do not use defaults! ). First, encrypt with scrypt and then encrypt it again with PGP (using different password!) in ASCII armor mode before print it (other methods like QR codes may not be reliable as multiple copies of the PGP ASCII armor). Do not use the same password for the PGP because it's easy to brute
Read more

[fixed] "Evolution is currently offline due to a network outage."

Evolution is currently offline due to a network outage. Evolution will return to online mode once a network connection is established. If you have this error when updating your system (for example, from Ubuntu 14 to Ubuntu 16), the solution is to run Evolution with this command: evolution --force-online That is usually related to a combination of evolution, dbus, and NetworkManager. With all three installed the idea was that NM would say whether it had a working network or not over dbus. Tools like evolution would ask on dbus about the state of the network and switch to online or offline as networks were hotplugged. This breaks down when the network isn't managed by NM but NM is still running. Such as when /etc/network/interfaces is configured to use ifupdown instead. If NM is running then it won't have any networks under its control and it fails to recognize that the system does actually have a network running outside of its control. It will respond to evolution
Read more

"The Uncensored Hidden Wiki" fake replica!

Image
I found out that there is a fake version of "The Uncensored Hidden Wiki". On the fake version some links are changed with fake websites. I suppose they are trying to steal your login credentials. I compared the "Financial services" pages on both wikis and found out that they changed the URL of the "Hidden Answers". However, the fake replica of "Hidden Answers" don't work at the moment.   Genuine (supposedly): http://gxamjbnu7uknahng.*****/wiki/index.php/Financial_Services Fake: http://uhwiki36pbooodfj.*****/wiki/index.php/Financial_Services   Please note that I do not guarantee which of the above URLs is "genuine" and don't assume that any of them are "safe". Maybe both of them are "fake", I don't know. Here are some examples of differences: Screenshots are from Meld . Visit "The Uncensored Hidden Wiki" or any other *.onion website at your own risk. I do not endorse and do not reco
Read more
[ad removed]