NoMachine up to 6.0.66_2 on Win7/Win8/Win10 DokanFS stack access control

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.3$0-$5k0.02

A vulnerability was found in NoMachine up to 6.0.66_2 on Win7/Win8/Win10. It has been declared as problematic. Affected by this vulnerability is an unknown functionality of the component DokanFS. The manipulation of the argument stack as part of a Variable leads to a access control vulnerability. The CWE definition for the vulnerability is CWE-264. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

An uninitialised stack variable in the nxfuse component that is part of the Open Source DokanFS library shipped with NoMachine 6.0.66_2 and earlier allows a local low privileged user to gain elevation of privileges on Windows 7 (32 and 64bit), and denial of service for Windows 8 and 10.

The bug was discovered 02/23/2018. The weakness was disclosed 02/28/2018 (Website). It is possible to read the advisory at nomachine.com. This vulnerability is known as CVE-2018-6947 since 02/13/2018. The exploitation appears to be easy. Attacking locally is a requirement. The exploitation doesn't need any form of authentication. Technical details and also a public exploit are known. The attack technique deployed by this issue is T1068 according to MITRE ATT&CK.

It is possible to download the exploit at exploit-db.com. It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 5 days. During that time the estimated underground price was around $0-$5k. The commercial vulnerability scanner Qualys is able to test this issue with plugin 370802 (NoMachine Un-initialised variable Privilege Escalation Vulnerability).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Exploit-DB (44167).

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.5

VulDB Base Score: 3.3
VulDB Temp Score: 3.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
unlockunlockunlockunlockunlockunlock
unlockunlockunlockunlockunlockunlock
unlockunlockunlockunlockunlockunlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-264
ATT&CK: T1068

Local: Yes
Remote: No

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Dayunlockunlockunlockunlock
Todayunlockunlockunlockunlock

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

02/13/2018 🔍
02/23/2018 +10 days 🔍
02/28/2018 +5 days 🔍
02/28/2018 +0 days 🔍
03/01/2018 +1 days 🔍
01/09/2020 +679 days 🔍

Sourcesinfo

Advisory: nomachine.com
Status: Not defined
Confirmation: 🔍

CVE: CVE-2018-6947 (🔍)
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 03/01/2018 08:00
Updated: 01/09/2020 15:16
Changes: 03/01/2018 08:00 (62), 01/09/2020 15:16 (5)
Complete: 🔍

Discussion

No comments yet. Languages: en.

Please log in to comment.

Do you need the next level of professionalism?

Upgrade your account now!