WARNING: UNPROTECTED PRIVATE KEY FILE! when trying to SSH into Amazon EC2 Instance

I've chmoded my keypair to 600 in order to get into my personal instance last night,

And this is the way it is supposed to be.

From the EC2 documentation we have "If you're using OpenSSH (or any reasonably paranoid SSH client) then you'll probably need to set the permissions of this file so that it's only readable by you." The Panda documentation you link to links to Amazon's documentation but really doesn't convey how important it all is.

The idea is that the key pair files are like passwords and need to be protected. So, the ssh client you are using requires that those files be secured and that only your account can read them.

Setting the directory to 700 really should be enough, but 777 is not going to hurt as long as the files are 600.

Any problems you are having are client side, so be sure to include local OS information with any follow up questions!

Make sure that the directory containing the private key files is set to 700

chmod 700 ~/.ec2

To fix this,

you’ll need to reset the permissions back to default: sudo chmod 600 ~/.ssh/id_rsa sudo chmod 600 ~/.ssh/id_rsa.pub If you are getting another error: Are you sure you want to continue connecting (yes/no)? yes Failed to add the host to the list of known hosts (/home/geek/.ssh/known_hosts). This means that the permissions on that file are also set incorrectly, and can be adjusted with this: sudo chmod 644 ~/.ssh/known_hosts

Finally, you may need to adjust the directory permissions as well: sudo chmod 755 ~/.ssh

This should get you back up and running.

The private key file should be protected. In my case i have been using the public_key authentication for a long time and i used to set the permission as 600 (rw- --- ---) for private key and 644 (rw- r-- r--) and for the .ssh folder in the home folder you will have 700 permission (rwx --- ---). For setting this go to the user's home folder and run the following command

Set the 700 permission for .ssh folder

chmod 700 .ssh

Set the 600 permission for private key file

chmod 600 .ssh/id_rsa

Set 644 permission for public key file

chmod 644 .ssh/id_rsa.pub

I also got the same issue, but I fix it by changing my key file permission to 600.

sudo chmod 600 /path/to/my/key.pem

Change the File Permission using chmod command

sudo chmod 700 keyfile.pem

On windows, Try using git bash and use your Linux commands there. Easy approach

chmod 400 *****.pem

ssh -i "******.pem" ubuntu@ec2-11-111-111-111.us-east-2.compute.amazonaws.com

Keep your private key, public key, known_hosts in same directory and try login as below:

ssh -I(small i) "hi.pem" ec2-user@ec2-**-***-**-***.us-west-2.compute.amazonaws.com

Same directory in the sense, cd /Users/prince/Desktop. Now type ls command and you should see **.pem **.ppk known_hosts

Note: You have to try to login from the same directory or you'll get a permission denied error as it can't find the .pem file from your present directory.

If you want to be able to SSH from any directory, you can add the following to you ~/.ssh/config file...

Host your.server
HostName ec2-user@ec2-**-***-**-***.us-west-2.compute.amazonaws.com
User ec2-user
IdentityFile ~/.ec2/id_rsa-gsg-keypair
IdentitiesOnly yes

Now you can SSH to your server regardless of where the directory is by simply typing ssh your.server (or whatever name you place after "Host").

Just to brief the issue, that pem files permissions are open for every user on machine i.e any one can read and write on that file On windows it difficult to do chmod the way I found was using a git bash. I have followed below steps

Remove user permissions chmod ugo-rwx abc.pem Add permission only for that user chmod u+rw run chmod 400 chmod 400 abc.pem

4.Now try ssh -i for your instance

I am thinking about something else, if you are trying to login with a different username that doesn't exist this is the message you will get.

So I assume you may be trying to ssh with ec2-user but I recall recently most of centos AMIs for example are using centos user instead of ec2-user

so if you are ssh -i file.pem centos@public_IP please tell me you aretrying to ssh with the right user name otherwise this may be a strong reason of you see such error message even with the right permissions on your ~/.ssh/id_rsa or file.pem

The solution is to make it readable only by the owner of the file, i.e. the last two digits of the octal mode representation should be zero (e.g. mode 0400).

OpenSSH checks this in authfile.c, in a function named sshkey_perm_ok:

/*
 * if a key owned by the user is accessed, then we check the
 * permissions of the file. if the key owned by a different user,
 * then we don't care.
 */
if ((st.st_uid == getuid()) && (st.st_mode & 077) != 0) {
    error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
    error("@         WARNING: UNPROTECTED PRIVATE KEY FILE!          @");
    error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
    error("Permissions 0%3.3o for '%s' are too open.",
        (u_int)st.st_mode & 0777, filename);
    error("It is required that your private key files are NOT accessible by others.");
    error("This private key will be ignored.");
    return SSH_ERR_KEY_BAD_PERMISSIONS;
}

See the first line after the comment: it does a "bitwise and" against the mode of the file, selecting all bits in the last two octal digits (since 07 is octal for 0b111, where each bit stands for r/w/x, respectively).

Just a note for anyone who stumbles upon this:

If you are trying to SSH with a key that has been shared with you, for example:

ssh -i /path/to/keyfile.pem user@some-host

Where keyfile.pem is the private/public key shared with you and you're using it to connect, make sure you save it into ~/.ssh/ and chmod 777.

Trying to use the file when it was saved elsewhere on my machine was giving the OP's error. Not sure if it is directly related.