Non-Alpha Encoder - Metasploit


This page contains detailed information about how to use the encoder/x86/nonalpha metasploit module. For list of all metasploit modules, visit the Metasploit Module Library.

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Module Overview

Name: Non-Alpha Encoder
Module: encoder/x86/nonalpha
Source code: modules/encoders/x86/nonalpha.rb
Disclosure date: -
Last modification time: 2018-08-30 01:22:24 +0000
Supported architecture(s): x86
Supported platform(s): All
Target service / protocol: -
Target network port(s): -
List of CVEs: -

Encodes payloads as non-alpha based bytes. This allows payloads to bypass both toupper() and tolower() calls, but will fail isalpha(). Table based design from Russel Sanford.

Module Ranking and Traits

Module Ranking:

  • low: The exploit is nearly impossible to exploit (or under 50% success rate) for common platforms. More information about ranking can be found here.

Basic Usage

msf > use encoder/x86/nonalpha
msf encoder(nonalpha) > show targets
    ... a list of targets ...
msf encoder(nonalpha) > set TARGET target-id
msf encoder(nonalpha) > show options
    ... show and set options ...
msf encoder(nonalpha) > exploit

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Msfconsole Usage

Here is how the encoder/x86/nonalpha module looks in the msfconsole:

msf6 > use encoder/x86/nonalpha

msf6 encoder(x86/nonalpha) > show info

       Name: Non-Alpha Encoder
     Module: encoder/x86/nonalpha
   Platform: All
       Arch: x86
       Rank: Low

Provided by:
  pusscat <[email protected]>

Description:
  Encodes payloads as non-alpha based bytes. This allows payloads to 
  bypass both toupper() and tolower() calls, but will fail isalpha(). 
  Table based design from Russel Sanford.

Module Options

This is a complete list of options available in the encoder/x86/nonalpha module:

msf6 encoder(x86/nonalpha) > show options

Module options (encoder/x86/nonalpha):

   Name  Current Setting  Required  Description
   ----  ---------------  --------  -----------

Advanced Options

Here is a complete list of advanced options supported by the encoder/x86/nonalpha module:

msf6 encoder(x86/nonalpha) > show advanced

Module advanced options (encoder/x86/nonalpha):

   Name       Current Setting  Required  Description
   ----       ---------------  --------  -----------
   VERBOSE    false            no        Enable detailed status messages
   WORKSPACE                   no        Specify the workspace for this module

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Error Messages

This module may fail with the following error messages:

Error Messages

Check for the possible causes from the code snippets below found in the module source code. This can often times help in identifying the root cause of the problem.

BadChar

Here is a relevant code snippet related to the "BadChar" error message:

43:	  #
44:	  def encode_block(state, block)
45:	    begin
46:	      newchar, state.key, state.decoder_key_size = Rex::Encoder::NonAlpha::encode_byte(block.unpack('C')[0], state.key, state.decoder_key_size)
47:	    rescue RuntimeError => e
48:	      raise BadcharError if e.message == "BadChar"
49:	    end
50:	    return newchar
51:	  end
52:	
53:	  #

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See Also

Check also the following modules related to this module:

Authors

  • pusscat

Version

This page has been produced using Metasploit Framework version 6.1.24-dev. For more modules, visit the Metasploit Module Library.

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