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Emanu

In the Hacking Windows 95, part 1 blog post, we covered that through a nasty bug affecting Windows 95/98/ME, the share password can be guessed in no time. In this article, I'm going to try to use this vulnerability to achieve remote code execution (with the help of publicly available tools only).

The first thing we can do when we have read access to the Windows directory through the share, is to locate all the *.pwl files on the c:\windows directory, copy them to your machine where Cain is installed, switch to Cracker tab, pwl files, load the pwl file, add username based on the filename, and try to crack it. If you can't crack it you might still try to add a .pwl file where you already know the password in the remote windows directory. Although this is a fun post-exploitation task, but still, no remote code execution. These passwords are useless without physical access.

One might think that after having a share password and user password, it is easy to achieve remote code execution. The problem is:

there is no "at" command (available since Windows 95 plus!)
there is no admin share
there is no RPC
there is no named pipes
there is no remote registry
there is no remote service management

If you think about security best practices, disabling unnecessary services is always the first task you should do. Because Windows 95 lacks all of these services, it is pretty much secure!

During my quest for a tool to hack Windows 95, I came across some pretty cool stuff:

Internet periscope

Winfingerprint

LanSpy

But the best of the best is Fluxay, which has been written by chinese hackers. It is the metasploit from the year 2000. A screenshot is worth more than a 1000 words. 4 screenshot > 4 thousand words :)

It is pretty hard to find the installer, but it is still out there!

But at the end, no remote code execution for me.

My idea here was that if I can find a file which executes regularly (on a scheduled basis), I can change that executable to my backdoor and I'm done. Although there is no scheduler in the default Windows 95, I gave it a try.

Let's fire up taskman.exe to get an idea what processes are running:

Looks like we need a more powerful tool here, namely Process Explorer. Let's try to download this from oldapps.com:

LOL, IE3 hangs, can't render the page. Copying files to the Win95 VM is not that simple, because there are no shared folders in Win95 VM. And you can't use pendrives either, Win95 can't handle USB (at least the retail version). After downloading the application with a newer browser from oldapps, let's start Process Explorer on the test Windows 95.

Don't try to download the Winsocks 2 patch from the official MS site, it is not there anymore, but you can download it from other sites.

Now let's look at the processes running:

After staring it for minutes, turned out it is constant, no new processes appeared.
Looking at the next screenshot, one can notice this OS was not running a lot of background processes ...

My current Win7 has 1181 threads and 84 processes running, no wonder it is slow as hell :)

We have at least the following options:

You are lucky and not the plain Windows 95 is installed, but Windows 95 Plus! The main difference here is that Windows 95 Plus! has built-in scheduler, especially the "at" command. Just overwrite a file which is scheduled to execution, and wait. Mission accomplished!
Ping of death - you can crash the machine (no BSOD, just crash) with long (over 65535 bytes) ICMP ping commands, and wait for someone to reboot it. Just don't forget to put your backdoor on the share and add it to autoexec.bat before crashing it.
If your target is a plain Windows 95, I believe you are out of luck. No at command, no named pipes, no admin share, nothing. Meybe you can try to fuzz port 137 138 139, and write an exploit for those. Might be even Ping of Death is exploitable?

Let's do the first option, and hack Windows 95 plus!

Look at the cool features we have by installing Win95 Plus!

Cool new boot splash screen!

But our main interest is the new, scheduled tasks!

Now we can replace diskalm.exe with our backdoor executable, and wait maximum one hour to be scheduled.

Instead of a boring text based tutorial, I created a YouTube video for you. Based on the feedbacks on my previous tutorialz, it turned out I'm way too old, and can't do interesting tutorials. That's why I analyzed the cool skiddie videoz, and found that I have to do the followings so my vidz won't suck anymore:

use cool black windows theme
put meaningless performance monitor gadgets on the sidebar
use a cool background, something related with hacking and skullz
do as many opsec fails as possible
instead of captions, use notepad with spelling errorz
there is only one rule of metal: Play it fuckin' loud!!!!

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Emanu

About BruteSpray: BruteSpray takes nmap GNMAP/XML output or newline seperated JSONS and automatically brute-forces services with default credentials using Medusa. BruteSpray can even find non-standard ports by using the -sV inside Nmap.

BruteSpay's Installation

With Debian users, the only thing you need to do is this command:
sudo apt install brutespray

For Arch Linux user, you must install Medusa first: sudo pacman -S medusa

And then, enter these commands to install BruteSpray:

Supported Services: ssh, ftp, telnet, vnc, mssql, mysql, postgresql, rsh, imap, nntpp, canywhere, pop3, rexec, rlogin, smbnt, smtp, svn, vmauthdv, snmp.

How to use BruteSpray?

First do an Nmap scan with -oG nmap.gnmap or -oX nmap.xml.
Command: python3 brutespray.py -h
Command: python3 brutespray.py --file nmap.gnmap
Command: python3 brutesrpay.py --file nmap.xml
Command: python3 brutespray.py --file nmap.xml -i

You can watch more details here:

Examples

Using Custom Wordlists:

python3 brutespray.py --file nmap.gnmap -U /usr/share/wordlist/user.txt -P /usr/share/wordlist/pass.txt --threads 5 --hosts 5

Brute-Forcing Specific Services:
python3 brutespray.py --file nmap.gnmap --service ftp,ssh,telnet --threads 5 --hosts 5

Specific Credentials:
python3 brutespray.py --file nmap.gnmap -u admin -p password --threads 5 --hosts 5

Continue After Success:
python3 brutespray.py --file nmap.gnmap --threads 5 --hosts 5 -c

Use Nmap XML Output:
python3 brutespray.py --file nmap.xml --threads 5 --hosts 5

Use JSON Output:
python3 brutespray.py --file out.json --threads 5 --hosts 5

Interactive Mode: python3 brutespray.py --file nmap.xml -i

Data Specs

{"host":"127.0.0.1","port":"3306","service":"mysql"} 
{"host":"127.0.0.10","port":"3306","service":"mysql"}
...

Changelog: Changelog notes are available at CHANGELOG.md.

You might like these similar tools:

Download BruteSpray

More info

Emanu

"snmpcheck is a free open source utility to get information via SNMP protocols. It works fine against Windows, Linux, Cisco, HP-UX, SunOS systems and any devices with SNMP protocol support. It could be useful for penetration testing or systems monitoring. snmpcheck has been tested on GNU/Linux, *BSD, Windows systems and Cygwin. snmpcheck is distributed under GPL license and based on Athena-2k script by jshaw. " read more...

Website: http://www.nothink.org/perl/snmpcheck

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Emanu

Tor enables users to surf the Internet, chat and send instant messages anonymously, and is used by a wide variety of people for both Licit and Illicit purposes. Tor has, for example, been used by criminals enterprises, Hacktivism groups, and law enforcement agencies at cross purposes, sometimes simultaneously.

Nipe is a Script to make Tor Network your Default Gateway.

This Perl Script enables you to directly route all your traffic from your computer to the Tor Network through which you can surf the Internet Anonymously without having to worry about being tracked or traced back.

Download and install:

    git clone https://github.com/GouveaHeitor/nipe
    cd nipe
    cpan install Switch JSON LWP::UserAgent

Commands:

    COMMAND          FUNCTION
    install          Install dependencies
    start            Start routing
    stop             Stop routing
    restart          Restart the Nipe process
    status           See status

    Examples:

    perl nipe.pl install
    perl nipe.pl start
    perl nipe.pl stop
    perl nipe.pl restart
    perl nipe.pl status

Bugs

Report bugs in my email: [hi@heitorgouvea.me]

Download Nipe

Continue reading

Emanu

In general decompilers are not friendly with c++ let's analyse a simple program to get familiar with it.
Let's implement a simple code that loads a file into a vector and then save the vector with following functions:

err
load
save
main

Lets identify the typical way in C++ to print to stdout with the operator "<<"

The basic_ostream is initialized writing the word "error" to the cout, and then the operator<< again to add the endl.

The Main function simply calls "vec = load(filename)" but the compiler modified it and passed the vector pointer as a parámeter. Then it bulds and prints "loaded " << size << " users".
And finally saves the vector to /tmp/pwd and print "saved".
Most of the mess is basically the operator "<<" to concat and print values.
Also note that the vectors and strings are automatically deallocated when exit the function.

And here is the code:

Let's take a look to the load function, which iterates the ifs.getline() and push to the vector.
First of all there is a mess on the function definition, __return_storage_ptr is the vector.
the ifstream object ifs is initialized as a basic_ifstream and then operator! checks if it wasn't possible to open the file and in that case calls err()
We see the memset and a loop, getline read a cstr like line from the file, and then is converted to a string before pushing it to the vector. lVar1 is the stack canary value.

In this situations dont obfuscate with the vector pointer vec initialization at the begining, in this case the logic is quite clear.

The function save is a bit more tricky, but it's no more than a vector iteration and ofs writing.
Looping a simple "for (auto s : *vec)" in the decompiler is quite dense, but we can see clearly two write, the second write DAT_0010400b is a "\n"

As we see, save implememtation is quite straightforward.

Read more

Prêt et crédit

Monday, August 31, 2020

Hacking Windows 95, Part 2

Sunday, August 30, 2020

BruteSpray: A Brute-forcer From Nmap Output And Automatically Attempts Default Creds On Found Services

More info

Snmpcheck

Saturday, August 29, 2020

Nipe - A Script To Make TOR Network Your Default Gateway

Reversing Some C++ Io Operations

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