[+] Credits: John Page aka hyp3rlinx

[+] Website: hyp3rlinx.altervista.org

[+] Source:
http://hyp3rlinx.altervista.org/advisories/HP-TOUCHSMART-CALENDAR-PRIVILEGE-ESCALATION.txt

[+] ISR: ApparitionSec



Vendor:
==========
www.hp.com



Product:
===========================================
Hewlett Packard TouchSmart Calendar Service
File version : 4.1.4245

HP TouchSmart Calendar is a shared calendar where you can manage your
familyas schedule. You can also view scheduled events for today
and tomorrow, e-mail calendar events with Google mail, and print your
schedule.



Vulnerability Type:
=====================
Privilege Escalation



CVE Reference:
==============
N/A



Vulnerability Details:
=====================

HP Calendar Service uses weak insecure permissions settings on its
files/directory as the aEveryonea group has full access on it.
Allowing low privileged users to execute arbitrary code in the security
context of ANY other users with elevated privileges
on the affected system.

Any user (even guest) will be able to replace, modify or change the file.
This would allow an attacker the ability to inject code
or replace the "HPTouchSmartSyncCalReminderApp.exe" executable and have it
run in the context of the system.


Proof...

c:\Windows\System32>sc query "HP Support Assistant Service"

SERVICE_NAME: HP Support Assistant Service
        TYPE               : 10  WIN32_OWN_PROCESS
        STATE              : 4  RUNNING
                                (STOPPABLE, NOT_PAUSABLE, ACCEPTS_SHUTDOWN)
        WIN32_EXIT_CODE    : 0  (0x0)
        SERVICE_EXIT_CODE  : 0  (0x0)
        CHECKPOINT         : 0x0
        WAIT_HINT          : 0x0


c:\>cacls "C:\Program Files
(x86)\Hewlett-Packard\TouchSmart\Calendar\Service"
C:\Program Files (x86)\Hewlett-Packard\TouchSmart\Calendar\Service
Everyone:(OI)(CI)F
                                                                   NT
AUTHORITY\SYSTEM:(OI)(CI)F



Disclosure Timeline:
======================================
Vendor Notification:  October 14, 2016
Vendor response: Product past warranty support
October 26, 2016 : Public Disclosure


Exploitation Technique:
=======================
Local



Severity Level:
================
Medium




[+] Disclaimer
The information contained within this advisory is supplied "as-is" with no
warranties or guarantees of fitness of use or otherwise.
Permission is hereby granted for the redistribution of this advisory,
provided that it is not altered except by reformatting it, and
that due credit is given. Permission is explicitly given for insertion in
vulnerability databases and similar, provided that due credit
is given to the author. The author is not responsible for any misuse of the
information contained herein and accepts no responsibility
for any damage caused by the use or misuse of this information. The author
prohibits any malicious use of security related information
or exploits by the author or elsewhere.

hyp3rlinx