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Debian passwd package sources - Unable to find patch that modifies passwd utility options

I noticed passwd utility doesn't support the -s/--stdin option on Debian which allows to read password from standard input. With this option you can do something like echo mypassword | passwd -s ...
designerrr's user avatar
0 votes
1 answer
36 views

How to syncronize credentials in a small laboratory? (very slim alternative to ldap)

We run a small lab with 20 Linux systems (RaspberryPI, NAS, Desktop PCs) for research with 4 scientists who all need sudo permissions. We trust all 4 users as they have sudo permission and physical ...
Jonas Stein's user avatar
  • 4,138
0 votes
1 answer
63 views

I've forgotten my password but am logged in--what tools can I use to assist in recovery and limit damages?

I have an encrypted hard drive. The hard drive, root user, and primary user all share the same password. I have successfully logged in but seem to have forgotten the password. I'm looking to limit the ...
mpr's user avatar
  • 1,154
0 votes
0 answers
41 views

How to calculate the password hash in /etc/shadow [duplicate]

I have the following line in my /etc/shadow file (SALT and HASHED_PASSWORD are not real values for obvious reason). And I understand $6 means SHA512 is used. testuser:$6$SALT$HASHED_PASSWORD:19591:0:...
DrizzleX's user avatar
  • 125
0 votes
2 answers
341 views

Difference between *LK* in /etc/shadow and /usr/sbin/nologon in /etc/passwd

What is the practical difference between setting *LK* in /etc/shadow and setting /usr/sbin/nologon in /etc/passwd? When would we choose one over the other? When would we combine them?
Lyubomir's user avatar
  • 113
0 votes
1 answer
146 views

Difference between passwd and passwd- file as well as shadow and shadow- file

on my server running UnraidOS I got a bit suspicious. There are both 'passwd' and 'passwd-' files (same goes for shadow(-)). These ones should be only backups as I understood. Running: root@Unraid-...
Dakanomo's user avatar
0 votes
0 answers
92 views

Password manager which gets unlocked by logging in into your session other than GNOME Keyring

Windows has a neat feature: it has a built-in password manager/storage which gets unlocked automatically when you log in. Are there any Linux applications which are linked to pam.d, so that entering ...
Artem S. Tashkinov's user avatar
0 votes
1 answer
103 views

Hashed passwords are NOT similar although the salt and password are similar

I had created two users on Linux with the same exact passwords, but when I looked at the /etc/shadow file, I found that the hashed values look different, although the salt file is the same. (Please ...
David Nicola's user avatar
-1 votes
1 answer
234 views

How to get user creation details

Kindly assist to to get user creation details (date and time) and users login details in Solaris 10
eliot's user avatar
  • 31
0 votes
1 answer
86 views

etc shadow file for passwd - calculate not only date but time

I want to know if there is a way to get the last password change date + time stamp ?
yolook_daemon's user avatar
3 votes
1 answer
1k views

Where is the system's "sys" user's password hash stored in Debian?

I want to get the password hash of the sys user in Debian (but the password is preferred). I heard that all password hashes are stored in the /etc/shadow file, but there isn't a password hash for the ...
Vad Sim's user avatar
  • 195
0 votes
1 answer
104 views

How to update user password with the file has password,without prompt key in?

I am using Debian 11,set password with shadow. I random generate password into file pas: cat pas "Th3P@ssw0rd" When I update password to normal user has sudo privilege, sudo passwd username ...
kittygirl's user avatar
  • 111
6 votes
1 answer
4k views

What does j9T mean in yescrypt (from /etc/shadow)?

Consider this Shadow string $y$j9T$PaFEMV0mbpeadmHDv0Lp31$G/LliR3MqgdjEBcFC1E.s/3vlRofsZ0Wn5JyZHXAol5 There are 4 parts id : y (yescrypt) param : j9T salt : PaFEMV0mbpeadmHDv0Lp31 hash : G/...
kelalaka's user avatar
  • 165
3 votes
1 answer
674 views

Accept both MD5 and SHA512 hashes is /etc/shadow

recently upgraded debian server with many users to a recent version. The old server used MD5 password hashes (the shadow passwords begin with $1$) and new one is configured to use SHA-512. I want to ...
Paweł's user avatar
  • 31
0 votes
1 answer
122 views

Shadow service "user 'ftp': directory '/srv/ftp' does not exist"

Once in a while, my server throws this error when trying to run the shadow service. I can delete the users (http and ftp) but they keep reappearing. I don't want to add the directories, nor do I need ...
TheChubbyPanda's user avatar
1 vote
1 answer
2k views

CentOS 7 - how to login as root

I have a CentOS 7 image on my local machine that I want to allow login as root. This is going to be a system dedicated for testing. I initially tried using rescue mode and added kernel param "...
some user's user avatar
  • 249
1 vote
0 answers
55 views

What does "?" meaning in /etc/shadow file in RHEL [duplicate]

What does ? meaning in /etc/shadow file in RHEL in second column? myuser:**?**:17968:0:99999:7::: I could find answer for X, *, !, but not for ?.
user477499's user avatar
12 votes
1 answer
29k views

The format of encrypted password in `/etc/shadow`

I see a hashed passphrase like the following in /etc/shadow. I don't quite understand its format. $y$j9T$F5Jx5fExrKuPp53xLKQ..1$X3DX6M94c7o.9agCG9G317fhZg9SqC.5i5rd.RhAtQ7 It is made of four parts as ...
user15502206's user avatar
0 votes
1 answer
148 views

Define the user with the specific password

I have the following users with password from /etc/shadow: userA:$5$FSRFdXhqehxiiFZV$SoIvO/4Y2tvOzIi.8p1Ud6AInQ3K5XT/WqVE5Zh4GT8:18388:0:99999:7::: userB:*:18388:0:99999:7::: userC:$6$SJRweUUklycIq1C$...
Anonymous's user avatar
5 votes
2 answers
2k views

What prevents me from just editing the /etc/shadow file in unencrypted systems? [duplicate]

Real dumb question, but suppose a computer with Linux does not have an encrypted hard drive. If I generated a hash with "openssl passwd", couldn't I just run a live version of Ubuntu and add ...
Victor Chavauty's user avatar
1 vote
1 answer
95 views

Encrypted password with no linked algorithm

I was reading the shadow file structure explained here. I was wondering what happens if, perhaps for some type of error or wrong manual changes, the $id field representing the hashing algorithm is ...
EagleOne's user avatar
  • 423
0 votes
1 answer
108 views

Need help with a script that uses passwd and shadow

I would like assistance with something I have to do. I need to verify if all users in passwd are also in shadow, if the primary group exists, if the homedir exists and if it belongs to the correct ...
UserAsker312's user avatar
0 votes
2 answers
619 views

How can I use existing password-sha256, to allow login authorisation?

My goal I have an old MySQL database with usernames and passwords hashed using sha256. I don't have the original passwords and it is not possible to learn them. This is a simple user migration from a ...
Sfp's user avatar
  • 103
1 vote
1 answer
455 views

Locked out: overwrote /etc/shadow and /etc/grub.d with pacnew

After all these years of using Linux, I have never goofed up this badly. I should have known better, I honestly don't know what I was thinking. While trying to fix a small error message I was getting (...
alrob's user avatar
  • 115
3 votes
1 answer
1k views

/etc/passwd.org, /etc/group.org, /etc/shadow.org files

On a Debian 10 server, which started as Debian 7 and updated whenever new version came out, I accidentally found these three files: /etc/passwd.org, /etc/group.org, /etc/shadow.org The backup files /...
Krackout's user avatar
  • 2,742
1 vote
1 answer
794 views

Why the /etc/nshadow file remains after changing root password?

I saw some abnormal thing after changing root password in linux. When I typed ls -al /etc/ | grep shadow after changing root password, the result is as below. -r-------- 1 root root 653 Mar 9 ...
John's user avatar
  • 13
1 vote
1 answer
4k views

Linux - create user with no password (login without password prompt)

I found many articles mentioning that user has no password after using passwd -d. While on some of my systems it indeed works (I can su from unprivileged accounts to them without giving password) on ...
Lapsio's user avatar
  • 1,323
1 vote
0 answers
298 views

Single digit in /etc/shadow file Solaris for password hash

In the /etc/shadow file, I should expect to see like below:- loginID:passwordHash:...... In the case of Solaris, passwordHash should be a 13-character hash value. What does it mean then, if on my ...
Timothy Wong's user avatar
2 votes
3 answers
1k views

sg: not found - Alpine Linux

I am trying to execute a command with a specific user group as described in the linked question (How to run a process with a specific group?) on Alpine Linux, but the system says "not found" ~/work $ ...
alessionossa's user avatar
3 votes
1 answer
339 views

Why does /etc/shadow uses user name instead of uid?

/etc/shadow contains the username, but not the uid. Is there a specific reason, why a char * field was chosen over an int? For direct username->password check this might be quicker, but for ...
DarkTrick's user avatar
  • 361
2 votes
1 answer
3k views

/etc/shadow is empty, yet I am prompted for password

I have a board (Pine64) on which I run my custom-built linux distribution (using buildroot). I configure root to have no password, and the resulting /etc/shadow file looks like this: root:::::::: ...
Avi Shukron's user avatar
16 votes
2 answers
27k views

Disable password on linux user with command

Based on /etc/shadow(5) documentation on the second (password) field: encrypted password If the password field contains some string that is not a valid result of crypt(3), for instance ! or *, the ...
trikelef's user avatar
  • 411
7 votes
1 answer
12k views

How to know if password in /etc/shadow is hashed with SHA or MD?

I want to know my /etc/shadow password hash if its SHA or MD or something else. From what I read, it is related to the $ sign, but I don't have any dollar signs. Im using Ubuntu 16 Example: user:0....
Batchen Regev's user avatar
1 vote
1 answer
409 views

Screen Lock Checks password file but not Active Directory

We have a Linux system running Centos 7 and have an issue with the screen lock. We have a multi-user environment where each user has their own account. The authentication is using our university ...
3dalliance's user avatar
37 votes
3 answers
8k views

When did Unix stop storing passwords in clear text?

When did Unix move away from storing clear text passwords in passwd? Also, when was the shadow file introduced?
ZDOSA's user avatar
  • 487
1 vote
2 answers
6k views

What is mean "x" in second field of /etc/shadow file [duplicate]

I have content in shadow file: root:!:17777:::::: bin:x:14871:::::: daemon:x:14871:::::: mail:x:14871:::::: ftp:x:14871:::::: http:x:14871:::::: dbus:x:14871:::::: nobody:x:14871:::::: systemd-...
Denis Proskurin's user avatar
4 votes
2 answers
2k views

How can the shadows around windows be removed from Mate with Lightdm?

There is a shadow around each window in Mate. If it matters I run Lightdm. How can the shadows be completely disabled for all windows regardless of the application?
user364407's user avatar
2 votes
1 answer
967 views

How to upgrade shadow package in Debian

I have been told one of my Docker images has "Docker security issue CVE-2017-12424", says one of its package shadow version is "1:4.4-4.1". And I need to upgrade. But I can only see version 1:4.4-4.1 ...
SmileSees's user avatar
3 votes
1 answer
1k views

Why is +::0:0::: not supposed to be found in /etc/passwd?

I was reading the BSI Security Guidelines (GERMAN), on NIS and it explicitly mentioned that one should prevent the entry +::0:0::: from occuring in the /etc/passwd file of the NIS server. From my ...
Jayrassic's user avatar
2 votes
1 answer
1k views

lightdm does not show users which have no shadow password

I have switched my virtual machine, to use a ldap server for authentication with sssd. I assumed with this setup I will not need to use local passwords anymore, as i can login with ldap authentication....
Mandragor's user avatar
  • 1,070
3 votes
1 answer
676 views

Blank root password disabled in modern distros?

Having read this: https://stackoverflow.com/questions/11700690/how-do-i-completely-remove-root-password I was under the impression that a blank root password, as in modifying the /etc/shadow file for ...
AlphaCentauri's user avatar
0 votes
0 answers
243 views

case-preserving linux usernames and hostnames

Is there a way to set pam library to do case-preserving username validation? Is there a way to set useradd command to accept and preserve the case of usernames? I know usernames and URLs are not OS ...
Necktwi's user avatar
  • 1,026
-8 votes
1 answer
204 views

Crack a user password [closed]

I need to crack a user password at /etc/shadow which is hashed in sha512 with specific known salt
mostafa elmadany's user avatar
3 votes
3 answers
18k views

What is the difference between /etc/shadow and /etc/passwd?

It seems to me that /etc/shadow and /etc/passwd contain the same data. Why are there two files? Are they different?
Rahul Kamboj's user avatar
0 votes
1 answer
200 views

ffcast and compton - a shadowy problem

So I have compton, a composite manager that I use to make things look prettier, mostly to add shadows to windows, and make things transparent. I also have ffcast, which I currently am using to make ...
ENBYSS's user avatar
  • 163
2 votes
2 answers
3k views

How to manage /etc/passwd file

Let's say I want to keep the /etc/passwd file divided into system users like admin, wheel, root etc., and by actual users all at the end. How do I do that? By creating subdirectories?
Denny's user avatar
  • 251
0 votes
1 answer
242 views

useradd command truncates the password mentioned with -p option

Command is as below, which is executed on wind river linux manchine. useradd vpatest -c Pav -g guest -G log -s /data/bin/cli.sh -p $6$cem^CM38$4YdQAPgu8EXNG3ecurYk4eN1sIiYNauBdHFRJew3l/...
BRT's user avatar
  • 43
0 votes
0 answers
34 views

Hyphen Suffix on file name [duplicate]

I decided to randomly take a look at my /etc directory, and I saw some entries like this: passwd passwd- shadow shadow- subgid subgid- I know they are hyphens (-) and not tildes (~). What are the ...
Sir Intellegence-BrainStormexe's user avatar
6 votes
1 answer
13k views

When I copy /etc/shadow to another system, is it possible to login with the according passwords?

I am asking, because I generated a live CD using the hash from an existing /etc/shadow, assuming I will then be able to login with the corresponding password, but apparently login fails.
user569825's user avatar
1 vote
2 answers
4k views

Change Shadow Password

I am looking for a sed command to change the line: userA:$6$lhkjhl$sdlfhlmLMHQSDFM374FGSDFkjfh/7mD/354dshkKHQSkljhsd.sdmfjlk57HJ/:95170:::::: to userA:$6$sLdkjf$576sdKUKJGKmlk565oiuljkljpi/9Fg/...
Med's user avatar
  • 135