Vulnerabilities > CVE-2016-8721 - OS Command Injection vulnerability in Moxa Awk-3131A Firmware 1.1

047910
CVSS 9.1 - CRITICAL
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
HIGH
Confidentiality impact
HIGH
Integrity impact
HIGH
Availability impact
HIGH
network
low complexity
moxa
CWE-78
critical

Summary

An exploitable OS Command Injection vulnerability exists in the web application 'ping' functionality of Moxa AWK-3131A Wireless Access Points running firmware 1.1. Specially crafted web form input can cause an OS Command Injection resulting in complete compromise of the vulnerable device. An attacker can exploit this vulnerability remotely.

Vulnerable Configurations

Part Description Count
OS
Moxa
1
Hardware
Moxa
1

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Command Line Execution through SQL Injection
    An attacker uses standard SQL injection methods to inject data into the command line for execution. This could be done directly through misuse of directives such as MSSQL_xp_cmdshell or indirectly through injection of data into the database that would be interpreted as shell commands. Sometime later, an unscrupulous backend application (or could be part of the functionality of the same application) fetches the injected data stored in the database and uses this data as command line arguments without performing proper validation. The malicious data escapes that data plane by spawning new commands to be executed on the host.
  • Command Delimiters
    An attack of this type exploits a programs' vulnerabilities that allows an attacker's commands to be concatenated onto a legitimate command with the intent of targeting other resources such as the file system or database. The system that uses a filter or a blacklist input validation, as opposed to whitelist validation is vulnerable to an attacker who predicts delimiters (or combinations of delimiters) not present in the filter or blacklist. As with other injection attacks, the attacker uses the command delimiter payload as an entry point to tunnel through the application and activate additional attacks through SQL queries, shell commands, network scanning, and so on.
  • Exploiting Multiple Input Interpretation Layers
    An attacker supplies the target software with input data that contains sequences of special characters designed to bypass input validation logic. This exploit relies on the target making multiples passes over the input data and processing a "layer" of special characters with each pass. In this manner, the attacker can disguise input that would otherwise be rejected as invalid by concealing it with layers of special/escape characters that are stripped off by subsequent processing steps. The goal is to first discover cases where the input validation layer executes before one or more parsing layers. That is, user input may go through the following logic in an application: In such cases, the attacker will need to provide input that will pass through the input validator, but after passing through parser2, will be converted into something that the input validator was supposed to stop.
  • Argument Injection
    An attacker changes the behavior or state of a targeted application through injecting data or command syntax through the targets use of non-validated and non-filtered arguments of exposed services or methods.
  • OS Command Injection
    In this type of an attack, an adversary injects operating system commands into existing application functions. An application that uses untrusted input to build command strings is vulnerable. An adversary can leverage OS command injection in an application to elevate privileges, execute arbitrary commands and compromise the underlying operating system.

Seebug

bulletinFamilyexploit
description### Summary An exploitable OS Command Injection vulnerability exists in the web application 'ping' functionality of Moxa AWK-3131A Wireless Access Points running firmware 1.1. Specially crafted web form input can cause an OS Command Injection resulting in complete compromise of the vulnerable device. An attacker can exploit this vulnerability remotely. ### Tested Versions Moxa AWK-3131A WAP Version 1.1 Build 15122211 ### Product URLs http://www.moxa.com/product/AWK-3131_Series.htm ### CVSSv3 Score 9.1 - CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H ### Details The ping feature of the Moxa AWK-3131A WAP web application is vulnerable to OS command injection. No obfuscation or encoding is needed - it appears there is no filtering of user input. Entering an OS command that is preceded with a ; results in the command being executed by the OS with root permissions. ### Exploit Proof-of-Concept (optional) An authenticated user may obtain a remote shell with root privilages by entering the following in the ping input box: ``` ; /bin/busybox telnetd -l/bin/sh -p9999 ``` then telnet to port 9999. The attacker will be connected to a /bin/sh shell as the root user, without needing to enter any credentials. ### Mitigation (optional) Exploitation of the vulnerable parameter requires authentication to the web application. However, commands are executed by the operating system as the root user, negating any user-level privilege enforcement by the web application. ### Timeline * 2016-11-14 - Vendor Disclosure * 2017-04-18 - Public Release ### CREDIT * Discovered by Patrick DeSantis of Cisco Talos.
idSSV:96530
last seen2017-11-19
modified2017-09-19
published2017-09-19
reporterRoot
titleMoxa AWK-3131A Web Application Ping Command Injection Vulnerability(CVE-2016-8721)

Talos

idTALOS-2016-0235
last seen2019-05-29
published2017-04-18
reporterTalos Intelligence
sourcehttp://www.talosintelligence.com/vulnerability_reports/TALOS-2016-0235
titleMoxa AWK-3131A Web Application Ping Command Injection Vulnerability