Re: user account disappeared
"J. Hellenthal via freebsd-security" <[email protected]>
| Newsgroups | gmane.os.freebsd.security.general |
|---|---|
| Message-ID | <[email protected]> |
https://www.unix.com/man-page/FreeBSD/8/pwd_mkdb/ -- J. Hellenthal The fact that there's a highway to Hell but only a stairway to Heaven says a lot about anticipated traffic volume. > On Feb 27, 2021, at 18:12, J. Hellenthal <[email protected]> wrote: > > Looks like your master passwd db is out of sync. > > Command is mkpwdb or something similar then run init q > > Personally it would seem someone got ahold of master.passwd and doesn’t know how it works or a port upgrade failed to complete properly updating the db > > -- > J. Hellenthal > > The fact that there's a highway to Hell but only a stairway to Heaven says a lot about anticipated traffic volume. > >> On Feb 27, 2021, at 15:23, Gareth de Vaux <[email protected]> wrote: >> >> Hi all, one of my users in a jail has mysteriously half disappeared. I've renamed the user to 'lostuser', the password hash, and the process it's running to protect privacy below: >> >> I suddenly can't log in over ssh: >> >> sshd[22485]: Invalid user lostuser from XYZ >> >> # su - lostuser >> su: unknown login: lostuser >> >> # ls -ld /home/lostuser >> drwx------ 8 1012 users 18 Jan 23 11:19 /home/lostuser >> >> $HOME still exists but only showing the userid. >> >> # egrep "1012|lostuser" /etc/passwd >> lostuser:*:1012:1000:User &:/home/lostuser:/usr/local/bin/bash >> >> # egrep "1012|lostuser" /etc/master.passwd >> lostuser:$6$9xxxxx/:1012:1000::0:0:User &:/home/lostuser:/usr/local/bin/bash >> >> Entries are still in /etc/*passwd ? >> >> # ls -l /etc/*passwd /etc/group >> -rw-r--r-- 1 root wheel 605 Nov 6 16:52 /etc/group >> -rw------- 1 root wheel 4092 Jan 23 12:22 /etc/master.passwd >> -rw-r--r-- 1 root wheel 2621 Jan 23 12:22 /etc/passwd >> >> This process is still running, which is a network server which is still functioning: >> >> # ps aux | grep lostuser >> 1012 56261 0.0 0.1 44952 21288 7 S+J 3Dec20 9:52.21 /usr/local/bin/python3.6 /home/lostuser/xyz >> >> also obviously showing the userid and not the username. >> >> >> # grep lostuser /var/log/auth.log >> ... >> Dec 31 10:56:34 ns1 sshd[43798]: Accepted publickey for lostuser from xyz >> Dec 31 10:56:57 ns1 sshd[44133]: Disconnected from user lostuser >> Jan 10 09:37:05 ns1 sshd[9679]: Accepted publickey for lostuser from xyz >> Jan 10 09:37:09 ns1 sshd[10241]: Disconnected from user lostuser >> Jan 23 11:19:11 ns1 sshd[45905]: Accepted publickey for lostuser from xyz >> Jan 23 11:19:14 ns1 sshd[46228]: Disconnected from user lostuser >> Feb 27 18:06:49 ns1 sshd[93323]: Invalid user lostuser from xyz >> Feb 27 18:06:49 ns1 sshd[93323]: Connection closed by invalid user lostuser xyz >> >> 23 Jan 2021 was the last successful login, and later that day /etc/*passwd was touched due to me changing the >> password of a different user, confirmed as the only change from diff'ing against backups. >> >> Last buildworld upgrade on 3 Nov 2020 (host and jail): >> >> $ uname -a >> FreeBSD ns1.lordcow.org 11.4-STABLE FreeBSD 11.4-STABLE #0 r367290: Tue Nov 3 12:11:29 SAST 2020 [email protected]:/usr/obj/usr/src/sys/GENERIC amd64 >> >> The last ports upgrade was 13 Feb 2021, before that I'm not sure. >> >> The last entry in /var/log/userlog was 23 Jul 2020, and: >> >> # ls -l /var/log/userlog >> -rw------- 1 root wheel 4202 Jul 23 2020 /var/log/userlog >> >> >> ie. timeline: >> >> 23 Jul 2020 Last userlog change >> 3 Nov 2020 buildkernel/buildworld and reboot >> 3 Dec 2020 lostuser network server process spawned and still functioning >> 23 Jan 2021 Last successful login to lostuser >> 23 Jan 2021 Unrelated user's password intentionally changed with passwd >> 13 Feb 2021 ports upgrade >> 27 Feb 2021 Discover user doesn't exist anymore but still has entries in /etc/*passwd and a process running >> >> Any ideas? >> _______________________________________________ >> [email protected] mailing list >> https://lists.freebsd.org/mailman/listinfo/freebsd-security >> To unsubscribe, send any mail to "[email protected]" _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-security To unsubscribe, send any mail to "[email protected]"