Vulnerability Note VU#316888

MobaXterm server may allow arbitrary command injection due to missing X11 authentication

Original Release date: 02 Nov 2015 | Last revised: 02 Nov 2015


The MobaXterm server prior to verion 8.3 is vulnerable to arbitrary command injection over port 6000 when using default X11 settings.


CWE-306: Missing Authentication for Critical Function - CVE-2015-7244

MobaXterm server prior to version 8.3 includes an X11 server listening on all IP addresses which does not authenticate remote X11 connections over port 6000. A remote attacker may silently connect to the server, and view and inject X11 commands with the privileges of the user currently using MobaXterm.


An unauthenticated remote attacker may view and inject X11 commands with the privileges of the user currently using MobaXterm.


Apply an update

Mobatek has released MobaXterm 8.3 which addresses this issue by notifying users of incoming connection attempts and allows the user to accept or decline. Affected users are encouraged to update as soon as possible.

Vendor Information (Learn More)

VendorStatusDate NotifiedDate Updated
MobatekAffected30 Sep 201516 Oct 2015
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base 7.5 AV:N/AC:L/Au:N/C:P/I:P/A:P
Temporal 5.9 E:POC/RL:OF/RC:C
Environmental 4.4 CDP:ND/TD:M/CR:ND/IR:ND/AR:ND



Thanks to Bryan Rhodes, Ryan Wincey, Micheal Reski, and Dan Mason for reporting this vulnerability.

This document was written by Garret Wassermann.

Other Information

  • CVE IDs: CVE-2015-7244
  • Date Public: 31 Oct 2015
  • Date First Published: 02 Nov 2015
  • Date Last Updated: 02 Nov 2015
  • Document Revision: 26


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