Ubuntu Security :: Disable Tunneled Clear Text Passwords
Nov 13, 2010
The ubuntu installation came with my ubuntu (it does not matter which version etc.) Contains sshd_config file with this interesting lines:
# Change to no to disable tunneled clear text passwords
#PasswordAuthentication yes
The same lines are seen in many Ubuntu-related internet pages. This is quite surprising to see.
This seem to contradict to the fact that ssh was created specially to provide authentication (with passwords, of couse) but without sending them by internet as clear text like previous programs did. But I could not find any clear confirmations of that neither in Kubuntu-related documents no anywhere else. I put below fragment of a document from RedHat. This seem to imply that if one will use two "yes", the passwords will be passed in encripted form (and this is what is recommended by RedHat). Is that true? Is this true for Ubuntu too? Is the quoted line from sshd_config wrong? Or incomplete?
[URL] RSAAuthentication yes
The option RSAAuthentication specifies whether to try RSA authentication. This option must be set to yes for better security in your sessions. RSA use public and private key pairs created with the ssh-keygen1utility for authentication purposes.
PasswordAuthentication yes
The option PasswordAuthentication specifies whether we should use password-based authentication. For strong security, this option must always be set to yes.
I am using an internal toy svn server, and svn client seems to be configured to store passwords in gnome-keyring by default. How can I disable it or at least switch to kwallet?I am using Debian Testing.
Running SunGard Banner software on RHEL 4.2 x86-32 bit Linux server Oracle Application 10.1.2.3 samba enabled. Users run processes/reports that are logged in a daily log file. In our daily job submission log files the user password shows up as clear text.The password shows up as $PSWD (sample from the logfile):
I use Ubuntu on my netbook, which I uses for browsing and email. It's way faster than the Windows which came on the machine. That's a nice feature, as is the price.
I like it except for the constant, perpetual, ever-present, super-annoying need to be entering passwords and "becoming root user" and so on. I am the only one using this appliance. I don't even care if someone steals it, really. There must be some way (I hope) of disabling this idea that I am a CIA agent with TopSecret materials.
I just want a simple, easy to use appliance. If not Ubuntu, is there any distro that is aimed at normal people?
When I'm logged in, physically on the server as root and logout the lines doesn't get cleared like when you logout as a normal user. This could be a bug and if it is, it could be a security problem. The last actions done shows.
Additional information:
Ubuntu Server 10.10 (32 bit) RAM: 1GB Server used as: webserver, database, gaming server.
I wonder if it is possible to have two passwords for one user account in 9.10. I have a long login password (5 words about 45 characters with spaces caps). I would like to set a shorter password for Authentication, sudo, etc. While retaining the original for logging in.In short:Have long password to login to computer.Have short password for everything after login.
I am not very security minded...I'm aware of it, and always made sure I had up-to-date overall protection in Windows but firewalls, and the blasted passwords are largely a thorn in my side!When I got my iPhone last year I suddenly discovered password managers & "wallets" to keep all that kind of information in and syncable across different devices. My life got so much easier. Of course now I need to figure out encryption keys, and how they work (I'm clueless). I also need to find a program or system that I can move my existing low-tech info (mailnly user name & passwords) that will also accomodate the increased needs of Ubuntu security and still be sync-able. I started a little research weeks ago, but my current "wallet" only exports .csv so I quit since I'm going to have to do a lot of data entry whatever I go with.So here goes:
1) what is the difference (bare bones) between using an encryption key (e.k.) vs. a standard user created password? what situations are better suited for e.k.?
2) I have seahorse (default intall with Ubuntu I guess) but the only thing in it is Login under passwords which leads to a login keyring (?) and a drop-down list of about 6-10 of the gazillon passwords I use daily. The other tabs are for keys which I don't have any concept of.
3) I know FF also "remembers" user id & passwords as you choose to have it do so. Is that information transferable into seahorse or another program?
4)I'm also (today) getting ready to really set up my system for user names & security across my little home network. How can I integrate that into whichever program/app I go with to store my pwds and keys?
5)give me links to fairly current documentation on this stuff?
6) Any program/app recommendations.Pros/cons uses, what they can & can't do or be used for, etc.
I've been meaning to ask about this since Ubuntu 10.10 launched. How come clicking the "Post message..." text box in the Me Menu doesn't auto-clear the text? You have to highlight the text, press Backspace and then post your message. Not very nice or intuitive. No biggie, just surprised it wasn't patched by someone within a day or two of launch as these things often are!
I have a headless server running Centos and I often login in remotely to administer it. I have passwordless login and sometimes run commands remotely via ssh from a client machine. I've tried to shut the server remotely but have come across a small problem. Here is the output of the command I use to shutdown :Code:unclec@linux-desktop $ ssh centos 'sudo /sbin/shutdown -h now 'PASSWORD : 123ABCAs passwordless login is set up I do not need to enter a password to ssh BUT as I am running sudo on the server I am asked to enter my centos unclec password and this is shown in clear text on my local machine terminal. Is there a way to prevent this or should I edit the sudoers file on centos so it does not ask me to enter the password when "sudoing" ?
I was wondering if there is way to hide passwords in bash scripts. For example: I have to write a script to export a full ldap structure, and I'm using the ldapsearch -y passwordfile, where password file is a plain text file that contains the password. Is there a way to hide the password from that file?
I was thinking to remove the r attribute from the file and before the script is lunched to put the attribute back, but is not a good solution, the same with immutable attribute.
I have set up my box to use ldap and I enter a users details in YaST and for the sake of simplicity I make the password 123456 The user gets created on the ldap server and everything seems Ok However I can't log in as that user and if I go to the ldap browser the password is in plain text Instead of saying {ssha}i345y9345yr34 or whatever is says {exop}123456
how do you clear the highlighted results after searching in elvis and other text viewer programs such as less?Also I know it's been mentioned before, but why does pat prefer elvis to vim? Just a personal preference?
Installing a router, and I need to completely "wipe" iptables (flush I mean) on both computers, and I think I run ufw/gufw on both, so that would need to be uninstalled. The router is very secure, has NAT, etc, etc, and I'd rather setup all that side of things in one point, rather than on each computer.
I think ubuntu/canonical should start releasing a new flavour geared towards meeting needs of computer security professionals just like backtrack distro
How would You encrypt Passwords [emails,forums,accounts] onto USB Flash the most Secure way? (It should be command line so I can use any Linux distribution on it.) Is gpg -c <filename> secure enough ? And what FAST distro would you install on it? I'm learning on old USB flash and found SliTaz pretty damn cool,I use it as a LiveUSB. Also I've tried Kubuntu but it's bit slow. Going to try Lubuntu soon too. Any other idea?
And I'd like to install some FAST distro onto new 8GB mini USB flash drive,maybe Kubuntu as well. How would you partition its Flash drive? Probably separate partition for stored encrypted files?
Is it possible to have two passwords associated with one account, one that is the actual one, and another one, a duress password, that upon entering gives a similar (desktop) environment with "decoy data"?
The idea is to have the bogus password go to an encrypted home drive that looks as if it were the real deal, but it is wiping particular sensitive (encrypted) data that is visible only with the real password in the background, so that the actual data that need to be protected are not compromised. While the person who unlocked the computer tries to find the information on it between all the rubbish files, the real files are securely wiped. The files are very sensitive in nature, so it's better to have then destroyed than have unauthorized people access them, in the event of that happening.
I happen to know that TrueCrypt has a similar option but that requires an entire decoy operating system (and I think that might be a bit conspicuous), but is there a native linux way to do it?
Lately I adapted my /etc/fstab to mount samba shared network drives. I had to put the password in the configuration file in order to log in automatically. Isn't there another way? It feels a little akward to me to put passwords in a plain text-file.
I would like to be able to store all my important details and passwords in such a way that it is encrypted, easy to get the information out and is cross-platform. Basically, I am thinking that if I kick the bucket that I would like to make it as easy as possible for others to be able to access this information using a pre-arranged password.
Ideally I would like the files to contain the program that is needed to extract the data i.e. importantinfoLinux.sh inportantinfoWin.exe (Just like a self-containing zip). I haven't found anything along those lines.
The things I am currently thinking of is:
1) A password database program that is cross-platform like KeePass. WIth the bundle contining the relevant installers for win, linux and OS X and the database file.
2) An AES encrypted zip of the data with relevant programs to open it e.g. 7-zip on windows, peazip on linux and OS X
Has anyone got any thoughts on this? Any self-containing java encryption apps?
As I am a paranoid bastard, I made a bash screencap-script for my Ubuntu-computer, so I can check if anyone uses my computer for things I don't want them to do (eg. checking if anyone is viewing passwords stored in FireFox, looking at private files, or other things I find disturbing). There might be other people than me that is paranoid and want to monitor what's going on on their computers while they are away or letting someone else use their computer when going to the bathroom.
This is a small script, I'd like to hear if there is any improvements that can be done, so I can learn more and become better at such scripting.
The script requires Imagick (sudo apt-get install imagemagick) and a folder in the ~-directory (/home/username) called ".screen" (hidden, as this makes it more difficult to "intruders" to find it and it looks more like a system-folder than a monitoring-folder).
The script:
Code: #!/bin/bash i=1; j=`date`; user=`whoami`;
[Code]....
Add this script to /usr/local/bin and then go to keyboard-shortcuts in GNOME and add a shortcut-key-combination of your own choice for the script. Call it whatever you'd like, and the command you want to run is simply "screen". To add a shortcut for stopping the script, you add another shortcut-key-combination to the command "killall screen".
This enables you to monitor activity on your computer while you're away, saving png-screenshots of your desktop every three seconds in the folder /home/username/.screen/date.
NOTE: I'm not taking any responsibility for what you do with this script. Remember that monitoring someone's activities is never the right way to handle anything. Also, it's illegal many places. Take care and use it only for educational and testing purposes.
if you go to Edit > prefs > security and choose to show saved passwords they are displayed without entering root pw. This seems to be a huge security hole. How do we fix this?
I'd like to know if something like this already exists :have an ecryptfs encrypted user account on a laptop that accepts two logins, 1st logs normally, the second triggers a system format
Sitting at the console, I log in with any user name and NO PASSWORD IS REQUESTED. I get logged in automatically without entering the user's password.
I did: passwd joeuser
To change his password and still he goes right in without being asked for a password!
Possibly related- 10 days ago, my smtp server was breached as a spam relay. The username they cracked was deleted. I added fail2ban for postfix. The logs show no further intrusion.
I have joined a number of websites over time and it seems harder to manage them. Would like advice on how to generate passwords and to store and keep track of them. I would like to hear of systems or programs that are good for this.
I'm trying to connect to my Ubuntu box from the WAN side with VNC tunneled through SSH. I've set up the port forward for SSH on the router and can successfully connect to SSH from the WAN side but when I try to forward my VNC session through SSH it times out or does not connect. On the LAN side I can also connect via SSH and also connect with VNC through SSH on LAN. Any ideas why I wouldn't be able to do the same from the WAN side when it works within the LAN? SSH port has been changed to 3250 and the VNC server is the defualt, Vino, with Ubuntu 10.10. The SSH command used was:
Code: ssh -L 5901:local-host-IP:5900 USER@WAN IP -p 3250 This followed with: localhost:5901 within the VNC client connecting to the box. This command worked fine within the LAN, substituting the WAN IP for the internal IP.
I'm looking for a tool, command line or GUI, for Linux that generates memorable passwords An equivalent of what I am looking for would be passwords that the Mac Os X keychain can generate, something like apples12$/fourteen. Something strong, but easily memorized by a user.
I'd like to know if there's a simple way to create a LUKS encryption drive with different passwords? A real one that leads to one set of data, and another that leads to a whole different set of data. Is this even possible with LUKS?
Is there a way to use kerberos (or baring that a trusted CA) to allow users to ssh across machines in an environment isntead of having to manage the hash keys per user/server? I'm using kerberos+ldap to log folks in and get their settings but I'd like to take it a step further. I've been reading a lot but still can't quite get it all to come together.
Do I need to create a SPN for each host to do this? Sorry if I am asking a dumb question, I am returning to the *nix fold after a decade+ in the Microsoft world, be gentle with me.
