ssh error while logging in using private key "loaded pubkey invalid format" and "error in libcrypto"?

Question

UPDATED

When I am trying to generate a public key it still gives me an error "error in libcrypto"

Load key "breakthis": error in libcrypto

Private key is given below

I am trying to solve a Hack the box machine

I was able to get a private key then I converted that private key into a hash for JOHNTHERIPPER and cracked it successfully

But now when I try to login in through ssh I am getting the following error I have searched a lot but not able to resolve these error

---

ssh -i id_rsa [email protected]

load pubkey "id_rsa": invalid format 

Load key "id_rsa": error in libcrypto

[email protected]'s password: 

---

Answer 1

In my case I had copied the keyfile using the clipboard, which had created a similar file but without terminating newline. That was enough to trip up libcrypto. Opening the file in vim and :wq closing it, was enough to add the newline, and it fixed my issue.

Answer 2

ERROR: load pubkey "id_rsa": invalid format

It happens when public key is used in ~/.ssh/config instead of using private key.

Answer 3

I fixed the Load key "id_rsa": error in libcrypto error by adding an LF control character (new line) at the end of the last line -----END OPENSSH PRIVATE KEY----- of the .pem file.

Before (doesn't work):

After (works):

Note the additional LF control character in the last non-empty line. One can add an LF control character by simply hitting the ENTER key.

Commands used to SSH into my remote computer:

chmod 400 key.pem
ssh -i "key.pem" [email protected]

Note: the error message can be either:

• Load key "id_rsa": error in libcrypto (I saw it on my Ubuntu computer).
• Load key "key.pem": invalid format (I saw it on my Windows computer) .

---

To show End of Line control characters in Notepad++:

Answer 4

I got this error, when I was using 2 github accounts with 2 ssh keys, but get rid of this error when i changed my config file like below,

myDir$ ssh -T [email protected]
Load key "/home/taxi/.ssh/mhmd_personal.pub": error in libcrypto
[email protected]: Permission denied (publickey).

From this

Host *
  AddKeysToAgent yes
  IdentityFile ~/.ssh/mhmd_personal.pub
  # IdentityFile ~/.ssh/id_ed25519

to

Host *
  AddKeysToAgent yes
  IdentityFile ~/.ssh/mhmd_personal
  # IdentityFile ~/.ssh/id_ed25519

removed the .pub extension from config file.

Answer 5

I just have fixed this problem. This problem was caused because of the format of the text.

Replace following the ssh-key format, Its looks like this:

-----BEGIN OPENSSH PRIVATE KEY-----
ENCODED KEY DATA HERE
-----END OPENSSH PRIVATE KEY-----

Answer 6

for future readers. I was using a ssh key file inside Gitlab CI YAML file and I kept getting error in libcrypto message. I did 2 things that FIXED the problem:

1. Just changing the variable type from FILE variable to ENV_VAR
2. Using ssh-keygen -t ed25519 when generating the key. Looks like gitlab does not support the default rsa keys.

Then everything works fine.

Also use this as the base before_script:

  before_script:
    - 'command -v ssh-agent >/dev/null || ( apt-get update -y && apt-get install openssh-client wget gnupg -y )'
    - wget -qO- https://get.docker.com/gpg | apt-key add -
    - eval $(ssh-agent -s)
    - echo "$SSH_PRIVATE_KEY" | tr -d '\r' | ssh-add -
    - mkdir -p ~/.ssh
    - touch ~/.ssh/config
    - touch ~/.ssh/known_hosts
    - chmod -R 400 ~/.ssh
    - ssh-keyscan <ip> >> ~/.ssh/known_hosts
    - '[[ -f /.dockerinit ]] && echo -e "Host *\n\tStrictHostKeyChecking no\n\n" > ~/.ssh/config'

Answer 7

what fixed it for me was the answer to this question

I opened the key in puttygen then exported a new ppk using the conversion --> Export OpenSSH Key

Answer 8

So in my case the private key file was simply missing the read permissions for the owner. After adding the read permission (chmod u+r id_ecdsa), everything worked fine.