Change Shadow Password

Question

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/rst3587zet324etze.dsfgLIMLmdf/:34650::::::

Is this hard-coded? Or are the changes you want in a bash variable? — SIGSTACKFAULT, Oct 18 '17 at 15:21
@Zachary Brady i will put it on a script to change the password for the same user on many servers — Med, Oct 18 '17 at 15:30
@Med I would use the passwd command to script mass password changes — Zachary Brady, Oct 18 '17 at 15:32
@Zachary Brady i had proposed the passwd command with EOF entry in my script but my manager refuse because he want me to use sed instead of password to avoid to put password in clear — Med, Oct 18 '17 at 15:40
On Linux, you can use chpasswd -e to give it the already-encrypted password. — Jeff Schaller, Oct 18 '17 at 15:50

score 5 · Accepted Answer · answered Oct 18 '17 at 15:51

instead:

chpasswd -e <<< 'userA:yourencryptedpassword'

If you were going to use sed - despite the risks:

To set a password - no matter what it was before:

sed -i.sedbackup 's/^\(userA:\)[^:]*\(:.*\)$/\1yournewpassword\2/' /etc/shadow

To replace a specific password string:

sed -i.sedbackup 's/^\(userA:\)youroldpassword\(:.*\)$/\1yournewpassword\2/' /etc/shadow

score 1 · Answer 2 · answered Feb 24 '21 at 10:11

1

Instead of the sed command you should do this:

usermod -p 'encrypted pw' user

answered Feb 24 '21 at 10:11

Stone

2 Answers2