Questions tagged [openssh]

Questions about the OpenSSH implementation of the ssh protocol.

Filter by
Sorted by
Tagged with
0 votes
0 answers
37 views

OpenSSH Connection Timed Out Issue

I am using Linux CentOS8 distribution. Openssh 8.0 installed on this server. When I try to connect via SSH to this server, connection timed out happens. I got a tcpdump and tcpdump shows that SSH ...
Mr.Peace's user avatar
0 votes
1 answer
45 views

Why are 3 entries added to ~/.ssh/known_hosts even though I use only a single key type?

I set up a new server (hostname: odroid) and copied my public ed25519 key to it. I signed to it for the first time and noticed 3 new entires have been added to ~/.ssh/known_hosts on my local machine: ...
Bartek Pacia's user avatar
-1 votes
1 answer
82 views

Why can't I scp a file to this host while I can ssh to it?

I configured sshd on my remote host with /etc/ssh/sshd_config.d/custom.conf: AddressFamily inet6 PermitRootLogin yes PubkeyAuthentication no Match Address fe80::d075:6982:4410:e071 This is a fresh ...
John Smith's user avatar
0 votes
1 answer
49 views

How to authenticate through OpenSSH then sudo with only one Ticket Service (Kerberos TGS host/fqdn)

By now, we are using OpenSSH GSSAPI authentication on all of our servers (Debian from 10 to 12). Then we sudo -i, using ldap authentication (through sssd-ldap). I would like to get rid of the ldap ...
neophenx's user avatar
0 votes
1 answer
92 views

Setting up a SSH Lab using docker on my local machine

I am using docker ubuntu container to set up an SSH lab on my local machine. I have interactively started the container and installed open ssh on it with other tools. I ensured that I port forward ...
sourabh dhingra's user avatar
0 votes
0 answers
18 views

How do I configure OpenSSH to not use the "-sk" versions of keys for hardware authenticators?

I have a system that needs to connect to several clients through SSH keys. This is in a somewhat legacy environment, and clients have varying OS and SSH versions. I created a new ed25519 host key on ...
jstarek's user avatar
  • 1,692
0 votes
1 answer
132 views

Log in to remote server by using a generated public key

I have a zsh script with which I logged into a remote host to copy some folders. The system asks me each time to give the password of the local host which I want to bypass, otherwise I have to enter ...
ecjb's user avatar
  • 383
0 votes
0 answers
89 views

SSH Keys Not Recognized?

I have two Debian (11 and 12) systems. I'm trying to verify ssh access from server A to server B via keys, following this video https://www.youtube.com/watch?v=vINn1MIrf7o. I try to use the keys, ...
Rez's user avatar
  • 1
0 votes
0 answers
38 views

key type ecdsa-sha2-nistp521 not in PubkeyAcceptedAlgorithms [preauth]

I have trouble setting passwordless authentication on a host: Sep 21 09:57:36 pvestorage2 sshd[1688625]: userauth_pubkey: key type ecdsa-sha2-nistp521 not in PubkeyAcceptedAlgorithms [preauth] OS: ...
Vatharian's user avatar
0 votes
0 answers
31 views

What are the OpenSSH ciphers default rekey transmission limit values?

The OpenSSH sshd_config man page says for RekeyLimits first argument: Specifies the maximum amount of data that may be transmitted before the session key is renegotiated [...] The default is between ‘...
Daku's user avatar
  • 81
1 vote
2 answers
66 views

Can two linux users share .ssh folder keys to connect to an SSH server

I have two linux users user1 - regular account with auth key stored in /home/user1/.ssh/ user2 - service account without home directory How can user2 access user1's keys to connect to the remote ...
try.aaam's user avatar
0 votes
1 answer
2k views

CentOS 7 upgrade openssh to 9.3p2

I am asked for an upgrade OpenSSH version because of CVE-2023-38408, here is my process.: yum groupinstall -y "Development Tools" yum install -y zlib-devel openssl-devel wget cp /etc/ssh/...
Chan's user avatar
  • 101
0 votes
0 answers
67 views

ssh-copy-id closed by remote host

I'm trying to copy public ssh with ssh-copy-id but it gives a connection close: user@serverA:~/ctm/cm/AFT/data/Keys$ ssh-copy-id -p 1222 -i /home/user/keys/serverA.pub vivek@serverB /usr/bin/ssh-copy-...
defekas17's user avatar
2 votes
1 answer
738 views

Are all Debian 11 systems automatically vulnerable to CVE-2023-38408?

I really really hope I'm wrong here, but it seems that Debian 11 has a vulnerable version of OpenSSH. My OpenSSH banner reports my OpenSSH version is: 8.4p1 Debian 5+deb11u1 I checked with sshd and it ...
Sir Muffington's user avatar
-1 votes
1 answer
52 views

Why does ls show this file twice with different sizes?

Why is 50-redhat.conf listed twice with different file sizes for this directory with this ls: ls -la /etc/ssh/ssh* -rw-r--r--. 1 root root 1921 Aug 2 02:58 /etc/ssh/ssh_config -rw-------. 1 ...
iletras's user avatar
  • 412
0 votes
0 answers
40 views

SSH not working outside of local machine

So, I'm trying to learn SSH. I don't have a public IPv4 address. So, I'm using my IPv6 address but SSH is only working inside my local machine. When I try it with WSL, it is showing ssh: connect to ...
lunix's user avatar
  • 29
0 votes
0 answers
36 views

Cannot login into SSH from non-admin account. /bin/bash: No such file or directory [duplicate]

Although I have found many other posts on this exact problem, none of their presented solutions have fixed my issue. I have configured and SFTP and SSH server on my raspberry pi. And ever since I ...
Kuba0040's user avatar
0 votes
0 answers
23 views

Incorrect MAC error while using ssh from windows to linux

I am trying to ssh from a windows system to an azure centos vm. But I am getting error incorrect MAC ... On further checking i identified it only happens when the mac algorithm used is umac-128-etm@...
Zez s Shin's user avatar
0 votes
2 answers
62 views

How can I map the sshd logs to my current ssh session?

I am exploring methods to correlate my current SSH session with the SSHD logs. I aim to extract specific information from the SSHD logs that pertain to my SSH session only. Jul 04 09:39:06 linuxbox ...
Karthick's user avatar
  • 123
1 vote
0 answers
66 views

Conditionally skip ssh-config options when ssh is too old for them?

How can I use SetEnv in ~/.ssh/config (and the same config on various systems), but not throw an error when ssh is too old to support it? I've tried adding a Match exec statement to exclude that ...
Jacktose's user avatar
  • 443
0 votes
0 answers
154 views

What is the difference between a Match all and a Host * block in ssh_config

As I was reviewing my current OpenSSH client configuration file and intensively reading the ssh_config(5) man page, I found that, from my understanding, both Match all and Host * will achieve the same ...
Étienne's user avatar
3 votes
1 answer
295 views

Does ssh client interfere with named pipes? [duplicate]

Setup: I have a system in bash where I have a single file that spawns off a pipeline of background processes. In stage one of the pipeline, there are multiple processes writing to a single named pipe. ...
Fury's user avatar
  • 33
-3 votes
1 answer
147 views

Use openssh for ssh connections and for public sftp

I have a system to which some users need to connect trough regular SSH. I will name them the “Privileged Users”. In the same time this system should provide an SFTP server to “Anonymous” user (without ...
fauve's user avatar
  • 1,150
0 votes
1 answer
161 views

How to make a script to forward commands to an SSH server?

I have a remote SSH server with several custom utilities for my work. However, there are times when I feel lazy and don't want to start a full SSH session just to execute a single command. This ...
JM0's user avatar
  • 201
3 votes
0 answers
326 views

Very odd SSH known_hosts verification failure with certificates

I recently upgraded one of my machines to latest Ubuntu 22.04, and now I am experiencing a very strange SSH server verification issue. Here is a short explanation of the situation. I am using SSH ...
Teemu Karimerto's user avatar
0 votes
1 answer
1k views

How do I convert an OpenSSH-generated ED25519 key to the PEM format?

I am trying to convert an OpenSSH-generated private host key to the PEM format, so that I can use it also in dropbear-initramfs. However, when trying to do so using the ssh-keygen program, I am ...
liori's user avatar
  • 612
0 votes
0 answers
55 views

Restrict user for ssh tunnelling

I'm trying to create a user without shell access just for port forwarding through ssh. The shell of the user is set to /usr/bin/false, but everytime i try to login through ssh it receive Permission ...
deodre's user avatar
  • 1
-1 votes
1 answer
21 views

Setting up a second computer with SSH keys once you've turned off password access

I'm new to managing Linux servers. After some research and study, I was able to generate SSH keys on my laptop and use those keys to successfully log into a new server that I'd just set up. Great. ...
dbates's user avatar
  • 111
1 vote
1 answer
405 views

How to restart sshd after assembly?

it is necessary to update the openssh server to the latest version, since everything is closed, it has come to manually assemble it ./configure --prefix=/usr --with-pam --with-selinux --with-privsep-...
Iceforest's user avatar
  • 113
0 votes
1 answer
1k views

Set default permissions for files received via SFTP

I'm receiving files pushed from another system via SFTP to a directory on a Linux VM. These files get the wrong permissions u=rw g= o=. However I need those files to have permissions like u=rw g=rw o=....
Niklas Letz's user avatar
0 votes
0 answers
128 views

Setting up SSH Password

I've been setting up ssh access to my desktop computer. I'm running a Debian Distro. I've enabled password authentication in the sshd_config file, and I've tried looking for the "keyboard-...
Lee's user avatar
  • 85
0 votes
1 answer
48 views

Why does ssh port forwarding fail?

In this example: $ ssh -L 8001:192.168.122.4:80 the output give is the default help: usage: ssh [-46AaCfGgKkMNnqsTtVvXxYy] [-B bind_interface] [-b bind_address] [-c cipher_spec] [-D [...
Sebi's user avatar
  • 999
0 votes
0 answers
58 views

ssh port forwarding using config

On a box the command line has been disabled and the ssh prompt is not accessible. What is the equivalent of: ssh> -L 8001:192.168.122.4:80 Port forwarding needs to be set up so that a host ...
Sebi's user avatar
  • 999
0 votes
1 answer
539 views

SSH freezes or won't even login

On a private network with a machine with private IP address 10.0.0.2 and a machine with 10.0.0.12 I encounter problems with SSH from 10.0.0.2 -> 10.0.0.12. The machine on 10.0.0.12 regularly ...
Postie's user avatar
  • 111
0 votes
0 answers
117 views

Midnight Commander: shell link connection not show dirs

Everything works fine when the target computer is windows 10 with cygwin and openssh 5.9p1-1 (libopenssl098 0.9.8t-1) [computer1]. After upgrading cygwin with openssh 1.1.1t-1 (libssl1.1 1.1.1t-1) [...
321Peto's user avatar
0 votes
0 answers
211 views

SSH/Cron services hangs on RHEL 8.6

So, i have an odd issue with my VM RHEL 8.6 test server with Hyper-V. The problem is the SSH Service hangs from time to time, around midnight. To connect again to the server i have to Reboot it ...
xnanitox's user avatar
  • 101
0 votes
0 answers
41 views

Individual connection of people via ssh

I have different users on the server and each of them has a username and password I want each user with his own username to be able to connect to the server with only one device at a time and not to ...
Hossein Sharbati's user avatar
0 votes
0 answers
96 views

Upgrading OpenSSH when OS version is outdated

I would like to upgrade OpenSSH version (currently version is OpenSSH_4.3p2, using protocol OpenSSL 0.9.8e-fips-rhel5). However, it seems I cannot upgrade it because OS Linux itself has a very old ...
Brice Tiki Abane's user avatar
0 votes
1 answer
495 views

Meaning of "key options: agent-forwarding" in OpenSSH logging

At first, I'd like to note that I am aware that there are a lot of other questions regarding SSH agent forwarding. The people there wanted to know how to make agent forwarding work or how to configure ...
Binarus's user avatar
  • 3,260
0 votes
1 answer
1k views

Missing libraries after installing openssl (libcrypto.so.1.1, ...)

I made my Arcolinux (5.12.14-arch1-1 x86_64) unusable by trying to install openssh. Googled a few hours and tried something, but without success. I did the following: $sudo pacman -S openvpn Then vpn ...
leol's user avatar
  • 3
0 votes
1 answer
509 views

how to restrict SSH for specific user from specific subnet

Is there any option to restrict SSH from specific user from specific subnet for example: [email protected]/24 needs to be disabled.
bhr's user avatar
  • 103
1 vote
0 answers
204 views

PKCS#11 provider in OpenSSH: Is it possible to cache PIN?

I use a RSA key on a smartcard with an OpenSSH client. The smartcard is read by a smartcard reader with a pinpad. The key is protected with a PIN. Is it possible to cache the PIN somehow? I don't ...
d.c.'s user avatar
  • 887
0 votes
1 answer
454 views

How to generate ssh key with AES-GCM?

I used that form to create my ssh key : ssh-keygen -t ed25519 -C "[email protected]" and I got: Encryption: aes256-cbc, is it possible to use [email protected] instead? thanks
James78's user avatar
  • 125
1 vote
0 answers
229 views

ssh does not use ssh-agent on FreeBSD

I recently set up a new FreeBSD system and am having a lot of trouble getting ssh to use ssh-agent. I have verified with ssh-add -l that my key is added, and the SSH_AGENT_PID and SSH_AUTH_SOCK env ...
Noldorin's user avatar
  • 107
0 votes
1 answer
93 views

SSH login still ask password even though public key is added in remote machine's ~/.ssh/authorized_keys file

I have a Raspberry pi 4 with a Linux OS & I am using a Macbook. The two machines are in the same LAN. Raspberry pi IP address is 192.168.10.11. I can ping the Raspberry Pi from my MacBook terminal ...
user842225's user avatar
0 votes
2 answers
365 views

ansible copy ssh keys to multiple users' home directory

I have ssh keypair on my ansible_host, which I want to copy to multiple user's authorized keys on target host. I'm trying with-item construct, but it complaints about .pub key not an invalid key here'...
Sollosa's user avatar
  • 1,899
2 votes
0 answers
287 views

Conditional inclusion in ssh_config

According to ssh_config(5) an Include statement can be placed inside a Match or Host block to create conditionsl inclusion Include: Include the specified configuration file(s). Multiple pathnames may ...
kvantour's user avatar
  • 131
3 votes
1 answer
3k views

How to read and debug SSH verbose-mode?

Let's say I use this command: ssh -vvv user@server I get an output similar to this: send packet: type 21 ssh_set_newkeys: mode 1 receive packet: type 6 SSH2_MSG_SERVICE_ACCEPT received receive packet:...
Pixelbog's user avatar
  • 669
0 votes
0 answers
513 views

How to install OpenSSH 8.3 Server on linux?

I am trying to install OpenSSH 8.3 server on linux. I downloaded the file from https://cdn.openbsd.org/pub/OpenBSD/OpenSSH/portable/ and have done all the steps from Install openssh-server 8.0p1 on ...
Anna's user avatar
  • 1
4 votes
1 answer
5k views

How to disable weak HMAC Algorithms? Not found in ssh_config or sshd_config file

A vulnerability scan showed that in a Debian 10 system, insecure MAC algorithms are in use: [email protected],[email protected],[email protected],hmac-sha1 When I do ssh -Q mac, I get ...
rocky_alpine's user avatar

1
2 3 4 5
16