Questions tagged [shadow]
Shadow passwords is a security feature commonly used on Unix and Linux systems.
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How to list mail adresses of active users on a Linux machine?
I'd like to get a list of mail addresses of all users, who are allowed to login. How can I do this?
I've set mail addresses in /etc/passwd using the GECOS field, i.e. via sudo chfn some_user -o ...
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Strange record in /etc/shadow after useradd -p and crypt function in bash script
Ubuntu 20.04 LTS.
There is a simple bash script to add a new user via command line in interactive mode:
#!/bin/bash
# Script to add a user to Linux system
if [ "$(id -u)" -eq 0 ]; then
...
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How to create a user and give it read permission to /etc/shadow file?
I would like to give my web server user (nginx) read access to the /etc/shadow file and I would like to confirm the steps that I am taking to do this. The system I am using is a CentOS 7.
First I ...
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What's !* in the password field in /etc/shadow?
Looking into my /etc/shadow file of a fairly new box today (running Arch), I see some passwords as * (disabled) but some others as !*, !! and as !. Presumably that means "disabled", too, but ...
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Add a second /etc/passwd + /etc/shadow + /etc/group combination
Is it possible to add a second /etc/passwd + /etc/shadow + /etc/group combination like this to a linux system?
/etc/passwd
/etc/passwd2
/etc/shadow
/etc/shadow2
/etc/group
/etc/group2
During ...
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1
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Why shouldn't LDAP support inequality searches on shadowExpire?
When I try to search my OpenLDAP 2.4.42 server for (shadowExpire<=18074), I get no results. However, a search for (shadowExpire=12671) yields several results.
My ultimate goal is to periodically ...
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1
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Linux custom NSS module, `_nss_SERVICE_getspnam_r` is called but `_nss_SERVICE_getpwnam_r` is not
I'm creating a custom NSS module. I managed to make it work on my local Redhat 7.3 box, configured nsswitch.conf correctly
passwd: files SERVICE
shadow: files SERVICE
and confirmed that both ...
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1
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Disabling logging in as root via kickstart? Advice recommendations?
This is a two part question. Firstly, I am just looking to validation, if I am doing this correctly since I am not sure how to test this. The goal is to disallow the login of the root account and have ...
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try to lock password but have no entry in /etc/shadow
Goal:
Maintaining a former colleagues system, I want to lock all password logins in order to only allow ssh key based logins.
Infos:
The CentOS 6.5 system does not offer any network based ...
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Linux to Samba Automatical Password Synchonization
Nothing found at all on the Net: I'm looking up for an automatical synchonization of linux to samba (NOT Samba to Linux) passwords.
I wrote a cgi web form that changes this password directly in the ...
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PAM vs /etc/shadow in Dovecot SASL configuration - Security differences?
I set up a server with Postfix SMTP auth through Dovecot SASL. However, it was not possible to get the PAM authentification working as standard out of the box.
So more by chance, I changed it to ...
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1
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Can't edit files /etc/passwd and /etc/shadow
I have some issues with files /etc/passwd and /etc/shadow. Both of them are without permissions:
---------- 1 root root 1357 Aug 5 11:30 passwd
---------- 1 root shadow 1175 Aug 5 11:30 shadow
...
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useradd not encrypting passwords in /etc/shadow
I stumbled accross this problem when trying to create new FTP users for vsftpd.
Upon creating a new user with the following command and attempting login with FileZilla, I would get an "incorrect ...
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Understanding linux /etc/shadow file structure (Linux) [closed]
Consider the following line taken from /etc/shadow file:
root:$1$NFEf74q.$bmukkxAq9dOMJINgEtP7u0:15258:0:::::
From this I understand that the hashing algorithm is md5 ($1) and starting from third $ ...
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Migrate user and passwords to new linux box
I am trying to migrate old Centos 4.3 box to Centos 7.
I have followed the migration steps from an article published way long back on http://www.cyberciti.biz/faq/howto-move-migrate-user-accounts-old-...
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passwd: Authentication token manipulation error
I am running a Ubuntu 12 machine, and have recently been working to secure it. I made all the changes from this guide. I am not running a Linode, but I used these as a starting point for setting up ...
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updating shadow file in a KVM guest in a mounted system
I have a KVM guest that I need to reset the password. If I use 'virsh console' to access the guest account, I'm able to update the shadow file with a new hash line like '$6$avdwsefs$...
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can't reset password from centos
I lost the root password. So I modified /etc/shadow and also changed '/etc/inittab' file to access single user mode. But both didn't work. It asked me for a password that I don't have. Why updating ...
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manually editing shadow file on disk from raid1 array
At work we have a machine to which root password has been lost. I have pulled out the disk and mounted it to another computer. Now I think the next step should be editing root password in the shadow ...
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NIS: which mechanism hides shadow.byname for unpriviledged users?
On some Linux box (SLES 11.1) which is a NIS client I can do as root:
ypcat shadow.byname
and get output, i.e. some lines with the encrypted passwords, amongst other information.
On the same Linux ...
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How are the hashes in /etc/shadow generated?
I was reading the Wikipedia article on the shadow file and it mentioned the format of the lines is like this:
$id$salt$hashed
So, my question is, how does it work?
I tried to calcualte the hash for ...
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Is there a way to prevent password expiration when user has no password?
Okay, we all care about security so users should change their passwords on a regular basis (who said passwords are like underwear?).
On redhat and centos (5.x and 6.x), it's possible to make every ...
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Change password hashing algorithm for SuSE users from blowfish to MD5
I have a network of roughly 1000 SuSE machines with 20-200 users on each. The password hashing algorithm used is the default i.e. blowfish. In order to check, whether a user has used a dictionary word ...
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How to generate a /etc/shadow compatible password for Ubuntu 10.04?
How are passwords generated that are used by Ubuntu 10.04? I know that they use SHA 512 as hashing algorithm, but I figure that there is some sort of salting done. I need to generate such a password ...
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3
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RHEL not accepting any passwords
I have RHEL 5 on virtual machine installed.
I was creating the new user by making entry in /etc/passwd.
I deleted the /etc/shadow file and used pwconv command to make new shadow file.
Now when i ...
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MySQL: Permit user to change his/her _own_ password
On a webserver there is a MySQL-service running, providing databases for the users of the server. Each user has it's own DB and it's own password and the right so INSERT/SELECT/UPDATE/DROP tables in ...
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Restore passwd for root on a server
I have a DVR server with linux embeded. It has some telnet functions but i don't have the password for it (the chinese manufacturer refuses to give me the password). ...
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What is the `shadow` group used for?
On my Ubuntu 9.10 system, there's a shadow system group. There does not appear to be any user assigned to this group at all. The only files that I can find belonging to this group are /etc/shadow and /...
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How should someone create an encrypted password for /etc/shadow?
I am setting up a new account on a Linux box for Subversion repository access, and can send the password to the new user. However, I think there was a command line utility for this new user to encrypt ...
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Diskless login with Linux/OpenSolaris
Is it possible to enable a Linux or OpenSolaris based server to process standard unix login requests without spinning up the hard drive holding the root partition?
I have a Nexenta-based (1) server ...