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Wednesday, April 15, 2020

Support For XXE Attacks In SAML In Our Burp Suite Extension

In this post we present the new version of the Burp Suite extension EsPReSSO - Extension for Processing and Recognition of Single Sign-On Protocols. A DTD attacker was implemented on SAML services that was based on the DTD Cheat Sheet by the Chair for Network and Data Security (https://web-in-security.blogspot.de/2016/03/xxe-cheat-sheet.html). In addition, many fixes were added and a new SAML editor was merged. You can find the newest version release here: https://github.com/RUB-NDS/BurpSSOExtension/releases/tag/v3.1

New SAML editor

Before the new release, EsPReSSO had a simple SAML editor where the decoded SAML messages could be modified by the user. We extended the SAML editor so that the user has the possibility to define the encoding of the SAML message and to select their HTTP binding (HTTP-GET or HTTP-POST).

Redesigned SAML Encoder/Decoder

Enhancement of the SAML attacker

XML Signature Wrapping and XML Signature Faking attacks have already been part of the previous EsPReSSO version. Now the user can also perform DTD attacks! The user can select from 18 different attack vectors and manually refine them all before applying the change to the original message. Additional attack vectors can also be added by extending the XML config file of the DTD attacker.
The DTD attacker can also be started in a fully automated mode. This functionality is integrated in the BurpSuite Intruder.

DTD Attacker for SAML messages

Supporting further attacks

We implemented a CertificateViewer which extracts and decodes the certificates contained within the SAML tokens. In addition, a user interface for executing SignatureExclusion attack on SAML has been implemented.

Additional functions will follow in later versions.

Currently we are working on XML Encryption attacks.

This is a combined work from Nurullah Erinola, Nils Engelbertz, David Herring, Juraj Somorovsky, and Vladislav Mladenov.

The research was supported by the European Commission through the FutureTrust project (grant 700542-Future-Trust-H2020-DS-2015-1).

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Linux Command Line Hackery Series - Part 6

Welcome back to Linux Command Line Hackery series, I hope you've enjoyed this series so far and would have learned something (at least a bit). Today we're going to get into user management, that is we are going to learn commands that will help us add and remove users and groups. So bring it on...

Before we get into adding new users to our system lets first talk about a command that will be useful if you are a non-root user.

Command: sudo
Syntax: sudo [options] command
Description: sudo allows a permitted user to execute a command as a superuser or another user.

Since the commands to follow need root privileges, if you are not root then don't forget to prefix these commands with sudo command. And yes you'll need to enter the root password in order to execute any command with sudo as root.

Command: useradd
Syntax: useradd [options] username
Description: this command is used for creating new user but is kinda old school.
Lets try to add a new user to our box.
[Note: I'm performing these commands as root user, you'll need root privileges to add a new user to your box. If you aren't root then you can try these commands by prefixing the sudo command at the very beginning of these command like this sudo useradd joe. You'll be prompted for your root password, enter it and you're good to go]

useradd joe

To verify that this command has really added a user to our box we can look at three files that store a users data on a Linux box, which are:

/etc/passwd -> this file stores information about a user separated by colons in this manner, first is login name, then in past there used to be an encrypted password hash at the second place however since the password hashes were moved to shadow file now it has a cross (x) there, then there is user id, after it is the user's group id, following it is a comment field, then the next field contains users home directory, and at last is the login shell of the user.

/etc/group -> this file stores information about groups, that is id of the group and to which group an user belongs.

/etc/shadow -> this file stores the encrypted password of users.

Using our command line techniques we learned so far lets check out these files and verify if our user has been created:

cat /etc/passwd /etc/group /etc/shadow | grep joe

In the above screenshot you can notice an ! in the /etc/shadow, this means the password of this user has not been set yet. That means we have to set the password of user joe manually, lets do just that.

Command: passwd
Syntax: passwd [options] [username]
Description: this command is used to change the password of user accounts.
Note that this command needs root privileges. So if you are not root then prefix this command with sudo.

passwd joe

After typing this command, you'll be prompted password and then for verifying your password. The password won't show up on the terminal.
Now joe's account is up and running with a password.

The useradd command is a old school command, lets create a new user with a different command which is kinda interactive.

Command: adduser
Syntax: adduser [options] user
Description: adduser command adds a user to the system. It is more friendly front-end to the useradd command.

So lets create a new user with adduser.

adduser jane

as seen in the image it prompts for password, full name and many other things and thus is easy to use.

OK now we know how to create a user its time to create a group which is very easy.

Command: addgroup
Syntax: addgroup [options] groupname
Description: This command is used to create a new group or add an existing user to an existing group.

We create a new group like this

addgroup grownups

So now we have a group called grownups, you can verify it by looking at /etc/group file.
Since joe is not a grownup user yet but jane is we'll add jane to grownups group like this:

addgroup jane grownups

Now jane is the member of grownups.

Its time to learn how to remove a user from our system and how to remove a group from the system, lets get straight to that.

Command: deluser
Syntax: deluser [options] username
Description: remove a user from system.

Lets remove joe from our system

deluser joe

Yes its as easy as that. But remember by default deluser will remove the user without removing the home directory or any other files owned by the user. Removing the home directory can be achieved by using the --remove-home option.

deluser jane --remove-home

Also the --remove-all-files option removes all the files from the system owned by the user (better watch-out). And to create a backup of all the files before deleting use the --backup option.

We don't need grownups group so lets remove it.

Command: delgroup
Syntax: delgroup [options] groupname
Description: remove a group from the system.

To remove grownups group just type:

delgroup grownups

That's it for today hope you got something in your head.

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Security Surprises On Firefox Quantum

This morning I've found an scaring surprise on my Firefox Quantum. Casually it was connected to a proxy when an unexpected connection came up, the browser was connecting to an unknown remote site via HTTP and downloading a ZIP that contains an ELF shared library, without any type of signature on it.

This means two things

1) the owner of that site might spread malware infecting many many people.
2) the ISP also might do that.

Ubuntu Version:

Firefox Quantum version:

The URL: hxxp://ciscobinary.openh264.org/openh264-linux64-0410d336bb748149a4f560eb6108090f078254b1.zip

The zip contains these two files:
3f201a8984d6d765bc81966842294611 libgmpopenh264.so
44aef3cd6b755fa5f6968725b67fd3b8 gmpopenh264.info

The info file:
Name: gmpopenh264
Description: GMP Plugin for OpenH264.
Version: 1.6.0
APIs: encode-video[h264], decode-video[h264]

So there is a remote codec loading system that is unsigned and unencrypted, I think is good to be aware of it.

In this case the shared library is a video decoder, but it would be a vector to distribute malware o spyware massively, or an attack vector for a MITM attacker.

DEFINATION OF HACKING

DEFINATION OF HACKING

Hacking is an attempt to exploit a computer system vulnerabilities or a private network inside a computer to gain unauthorized acess.
Hacking is identifying and exploiting weakness in computer system and/ or computer networks for finding the vulnerability and loopholes.

Continue reading

CEH: Identifying Services & Scanning Ports | Gathering Network And Host Information | NMAP

CEH scanning methodology is the important step i.e. scanning for open ports over a network. Port is the technique used to scan for open ports. This methodology performed for the observation of the open and close ports running on the targeted machine. Port scanning gathered a valuable information about the host and the weakness of the system more than ping sweep.

Network Mapping (NMAP)

Basically NMAP stands for Network Mapping. A free open source tool used for scanning ports, service detection, operating system detection and IP address detection of the targeted machine. Moreover, it performs a quick and efficient scanning a large number of machines in a single session to gathered information about ports and system connected to the network. It can be used over UNIX, LINUX and Windows.

There are some terminologies which we should understand directly whenever we heard like Open ports, Filtered ports and Unfiltered ports.

Open Ports means the target machine accepts incoming request on that port cause these ports are used to accept packets due to the configuration of TCP and UDP.

Filtered ports means the ports are usually opened but due to firewall or network filtering the nmap doesn't detect the open ports.

Unfiltered means the nmap is unable to determine whether the port is open or filtered while the port is accessible.

Types Of NMAP Scan

Scan Type	Description
Null Scan	This scan is performed by both an ethical hackers and black hat hackers. This scan is used to identify the TCP port whether it is open or closed. Moreover, it only works over UNIX based systems.
TCP connect	The attacker makes a full TCP connection to the target system. There's an opportunity to connect the specifically port which you want to connect with. SYN/ACK signal observed for open ports while RST/ACK signal observed for closed ports.
ACK scan	Discovering the state of firewall with the help ACK scan whether it is stateful or stateless. This scan is typically used for the detection of filtered ports if ports are filtered. Moreover, it only works over the UNIX based systems.
Windows scan	This type of scan is similar to the ACK scan but there is ability to detect an open ports as well filtered ports.
SYN stealth scan	This malicious attack is mostly performed by attacker to detect the communication ports without making full connection to the network. This is also known as half-open scanning.

All NMAP Commands

Commands	Scan Performed
-sT	TCP connect scan
-sS	SYN scan
-sF	FIN scan
-sX	XMAS tree scan
-sN	Null scan
-sP	Ping scan
-sU	UDP scan
-sO	Protocol scan
-sA	ACK scan
-sW	Window scan
-sR	RPC scan
-sL	List/DNS scan
-sI	Idle scan
-Po	Don't ping
-PT	TCP ping
-PS	SYN ping
-PI	ICMP ping
-PB	ICMP and TCP ping
-PB	ICMP timestamp
-PM	ICMP netmask
-oN	Normal output
-oX	XML output
-oG	Greppable output
-oA	All output
-T Paranoid	Serial scan; 300 sec between scans
-T Sneaky	Serial scan; 15 sec between scans
-T Polite	Serial scan; .4 sec between scans
-T Normal	Parallel scan
-T Aggressive	Parallel scan, 300 sec timeout, and 1.25 sec/probe
-T Insane	Parallel scan, 75 sec timeout, and .3 sec/probe

How to Scan

You can perform nmap scanning over the windows command prompt followed by the syntax below. For example, If you wanna scan the host with the IP address 192.168.2.1 using a TCP connect scan type, enter this command:

nmap 192.168.2.1 –sT

nmap -sT 192.168.2.1

Tuesday, April 14, 2020

Diggy - Extract Enpoints From APK Files

Diggy can extract endpoints/URLs from apk files. It saves the result into a txt file for further processing.

Dependencies

apktool

Usage

./diggy.sh /path/to/apk/file.apk

You can also install it for easier access by running install.sh
After that, you will be able to run Diggy as follows:

diggy /path/to/apk/file.apk

Download Diggy