JAWS Weak Service Permissions leads to Privilege Escalation

[Heimbuecher003@xxxxxxxxxxxxxxxx]

JAWS Weak Service Permissions leads to Privilege Escalation

Vendor Website : http://www.freedomscientific.com/Products/Blindness/JAWS


INDEX
===============================================
1. Background
2. Description
3. CVSS 3.0 Base Metrics
4. Affected Products
5. Vulnerability
6. Solution
7. Credit
8. Disclosure Timeline


1. BACKGROUND
===============================================
JAWS, Job Access With Speech, is the world's most popular screen reader, 
developed for computer users whose vision loss prevents them from seeing screen 
content or navigating with a mouse. 

2. DESCRIPTION
===============================================
When JAWS is installed on a Microsoft Windows operating system, it creates a 
service named "JTVNCProxy_version", where version is the current version of 
JAWS (e.g JTVNCProxy_13.0).

A local privilege escalation vulnerability has been identified in the 
JTVNCProxy Windows service in JAWS version 13.0 and earlier. When installed, 
this service allows Read/Write access to any user, meaning any user can modify 
the location of the binary executed by the service with SYSTEM privileges.

It should be noted that this vulnerability is not present in versions of JAWS 
from version 14 onwards.

3. CVSS 3.0 Base Metrics
===============================================
(AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H) 8.8

4. AFFECTED PRODUCTS
===============================================
All versions of JAWS 13 and earlier have been confirmed vulnerable.
 
 
5. VULNERABILITIES
===============================================
5.1 JTVNCProxy.exe

6. SOLUTION
===============================================
Vendor will provide a free upgrade to JAWS 14 for customers who are only 
licensed for JAWS 13 or earlier. Users interested in this free upgrade should 
contact support@xxxxxxxxxxxxxxxxxxxxx with their JAWS serial number and 
reference this disclosure.

7. CREDIT
===============================================
This vulnerability was discovered by Gregory Heimbuecher of Western Connecticut 
State University.

8. DISCLOSURE TIMELINE
===============================================
3-30-2016 - Vulnerability Discovered
4-1-2016 - Vendor Informed
4-4-2016 - Vendor acknowledges vulnerability, and announces a free upgrade to 
JAWS 14 for customers who are only licensed for JAWS 13 or earlier.
4-8-2016 - Public Disclosure