Cyberis Blog
Reassuringly clear thinking.
- Penetration testing
- Tools and techniques
User Enumeration - Timing Discrepancies
I find myself writing this blog today as there are only a few references on the internet to user enumeration attacks via timing discrepancies, despite almost every site I've tested in my career being vulnerable to the weakness. The issue is fairly obvious from the title; an application log-in response takes differing amount of times depending on whether or not the user is valid. But why?
- Red teaming
- Tools and techniques
Attacking Big Business
Reputational filtering typically blocks websites known to be malicious, performs antivirus scanning of all traffic, and crucially for us in respect to performing a simulated attack, warns end-users when visiting "non-categorised" sites. Any URLs and domains used as part of an attack now require user interaction in a web browser. This effectively rules out using newly stood up infrastructure both at the delivery and exfiltration stages of an attack, as these activities are performed without the victim's knowledge. The only options left to the attacker would be to "build" reputation over time, or alternatively, cheat the system.
- Penetration testing
PHP Serialization And SQL Injection
Sanitisation of user input is essential for preventing SQL injection, regardless of the format of the supplied data. Today I'm going to look at SQL injection through a more obscure injection point: serialized PHP arrays. Taking inspiration from a finding in a recent test, I've created a small app which allows the user to upload a CSV file. This file is then converted to a PHP array, serialized and returned to the user as a hidden form field. Finally, this is posted back to the application where the supplied data is inserted into the MySQL database.
- Penetration testing
- Tools and techniques
Creating Macros For Burp Suite
There are many tools available for automated testing of web applications. One of the best known is probably sqlmap. Sqlmap allows you to identify and exploit SQL injection vulnerabilities with ease from the command line. However, controls such as CSRF tokens or simple anti-automation techniques such as including a unique hidden value within the form can prevent automated tools from working correctly. Macros in Burp Suite are a great way to bypass these measures in order to carry out automated testing, although they can be complicated to implement.
- Detect and respond
After the storm
You’ve had an incident. You’ve managed the fall-out, contained the outbreak and restored normal service. Now is the time to sit down with your incident response teams, your operational teams and other stakeholders and work out how to prevent a recurrence.
- Detect and respond
Enacting your response
Situational awareness throughout incident response activities is of paramount importance. As activities are conducted, new information is likely to emerge. New information may completely change the objectives of your exercise, and teams need to be in constant communication in order to coordinate activities. Actions assigned to responders during an incident will be informed by the systems and data at risk, business continuity plans for these systems, and the objectives of the incident response exercise.
- Detect and respond
Defining your objectives
You have an incident. You know you need to handle it. You’re under pressure, and your team is stressed. This is often the most dangerous point in an incident response operation. Stressed people under pressure to respond quickly tend to make one of two mistakes...
- Detect and respond
Identifying the incident
At some point, your business is likely to have to deal with an incident. When this happens, being able to accurately identify and classify the incident is key to responding effectively with the minimum impact to your BAU operations. Yesterday, we discussed how proper planning will help you get a robust incident response framework in place. Today, we are going to look at the sorts of questions you need to ask yourselves in order to be able to identify and classify an incident, and hence tailor your response.
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