Bypassing SSL Pinning and Traffic Redirection to Burp Suite using MobSF and Genymotion

In the usual web application security testing, testers take advantage of proxy tools such as Burp Suite or OWASP Zap to tamper with the parameter of HTTP requests to the server and observe the traffic. There are also built-in scanning tools and add-on/plugins that can be integrated for more specific tests. For a web application that uses certificates, the resolution is to add Burp’s certificate to the trusted certificates so the traffic can still pass through the proxy.

However, when doing security tests in mobile apps, this can be a problem. A lot of mobile apps that use certificates implement SSL pinning, thus, it will not connect to the proxy as it doesn’t recognize it as a legitimate connection. Installing Burp’s certificate in the browser will not do any good as the mobile app does not pass through the mobile browser. There are different approaches to resolving this issue. One is to root the OS and install Burp’s certificate in the System Certificate list. By default, Burp’s certificate can only be installed in the User Certificate list if the OS is not rooted. The other approach is to disassemble the .apk file (assuming Android) using apktool and Frida, then disabling the SSL pinning there or referring to Burp’s Certificate as valid.

Depending on the setup, approach 1 or 2 may work. But the steps and tools may be complex as you need to disassemble and assemble the code back again. There are times when you need to do trial and error just to find out which approach or tweaks will work.

MobSF Dynamic Analysis

One of the tools I found is the Mobile Security Framework. It is a security tool that contains both static and dynamic analysis for Android, iOS, and Windows. What I like about the tool is that it automates the disassembling part and analysis of the Manifest and other parts of the code. It also has a risk scoring based on OWASP Mobile Top 10 and CVSS.

One of the more important features is the dynamic analysis. It can execute the uploaded APK to an emulator and execute runtime tests. Note that for dynamic analysis to work, MobSF must be installed in the host and not in a Guest/VM.

Bypassing SSL Pinning

Bypassing SSL Pinning is easy once you have set up the Dynamic Analysis feature of MobSF. Frida is already built-in and you can see the logs. In the example, we uploaded Wikipedia’s APK for static and dynamic analysis. When you start to. There are default settings such as API Monitoring, SSL Pinning Bypass, Root Detection Bypass, and Debugger Bypass.

Go to Frida Live Logs to see the status of the functions implemented. Browse through the mobile app in Genymotion and see the updates in the Frida Live Logs. It will also indicate if SSL Pinning has been bypassed.

Sending the HTTP/S Requests to Burp Suite

After bypassing SSL Pinning, we can now redirect the traffic to a proxy such as Burp Suite. You can go to Generate Report and go to HTTP(S) traffic to verify whether requests and responses are recorded. Once verified, you can go to Start HTTPTools to send the repeat the request to a proxy.

From there you can send the captured traffic to the Fuzzer by setting the IP and port used by the proxy (usually localhost:8080). Just make sure that you have the same set up in the proxy and toggle the Intercept button to “off” and you’re good to go.

Conclusion

These key features of MobSF will help security testers in analyzing the traffic of mobile applications. The tedious task of manually disassembling and assembling the app is resolved and more time can now be allocated to testing the logic and flow of the application.

Securing the Organization’s IT Assets Amidst COVID-19

man having a video call on his phone
Photo by Edward Jenner on Pexels.com

How should organizations conduct operations during a pandemic? How should organizations secure their IT assets during a pandemic? For big multinational companies, they have their respective Business Continuity Plans (BCP) that assist them in times like lockdowns, quarantines, or any disruptions to normal business activities. However, a lot of companies were caught off-guard and they were not able to smoothly transition to the “quarantine mode.”

How organizations are affected by COVID-19

According to an April 2020 report from Accenture about the effects of COVID-19 to organizations, there are significant impacts on system resilience and business continuity from the perspective of technology.  On a survey that they conducted in 2019 on system resilience, only 10% of the 8,300 respondents answered that their technology is resilient.  They summarized the effects on IT based on the following: business continuity risks, a surge in transaction volumes, workforce productivity challenges, and security risks.
Common cybersecurity issues faced

Phishing, scams, malware, access to malicious/bogus sites unknowingly are the common cybersecurity issues that organizations faced during the pandemic. Attacks on NASA have been reported consistently since the spread of COVID-19. Local banks like BPI, have issued a memo warning customers of phishing attacks that spoof BPI online platforms.  Google reported that there were 18 million malware detected in a week that are related to COVID-19. Trend Micro also reported a surge in COVID-19 themed attacks ranging from spam, malware, and malicious domains. Worse, unscrupulous individuals host COVID-19 case trackers and fill it with malware so visitors will be infected as they visit.

The following are the major cybersecurity issues organizations face:

  • Increased number of phishing and malware attacks that use COVID-19 as bait or theme.
  • There is an increase in cybersecurity risks because employees are in their homes which IT has a hard time managing. On the other end, support on the company networks will also be lessened because of reduced IT staffing.
  • Remote work/Work from home security issues.

Cybersecurity defense against attacks

SANS has created the SANS Security Awareness Deployment Guide that is very useful for organizations and employees during this time of reduced IT staff and work from home for a lot of employees. It contains all the materials that organizations will need such as templates, fact sheets, posters, and messaging for employees. It even has short learning videos that are very informative covering wide topics on social engineering, securing your home, and working remotely.

It is alarming to note as well that a lot of big multinational companies mentioned in the introduction whose technology and security maturity are both at the top of the line still suffer a lot of cybersecurity attacks such as phishing and malware. They have the best industry-grade anti-malware with a lot of advanced features, encryption in the hard drive level, and other security tools. But as we say in security, the technology is just as strong as the weakest link, which is the people. We have to emphasize the need for a consistent and periodic Security Awareness for employees especially now that the IT/Security team has a limited view of the organization’s assets.

It is also important that the IT/Security team should be accessible not only for support but for security incidents. Attacks can be well-planned and it can target certain people in the organization. Reporting the information about security incidents will help IT/Security team to respond promptly and make important communication to the stakeholders to prevent others from being victimized.

There also has to be clear guidelines/policies for employees. Remote work is a different and new environment that may need further and detailed guidance. For example, should users be allowed to connect to public Wi-Fi? Or are they only allowed to access their home network? If they are only allowed to use their home network, what necessary configurations should be done? A clear policy/guideline will be very helpful.

Management support is also of utmost importance. Quick and immediate approval of policies/guidelines is necessary for this volatile time. Budget is also a key element especially when you need to procure additional security software licenses. Management can provide both approval and budget.

The following are some of the security issues that need to be discussed with employees to take note of:

Social Engineering – Phishing, spear phishing, vishing, CEO fraud, and USB drop are some of the non-technical attacks that can target your organization. Employees must be trained on how to spot these attacks and report them immediately to the IT/Security team. Usual ways to spot these attacks include a strong sense of urgency, pressuring you to violate a policy, generic e-mail, brief message, and use of personal e-mail.

Passwords – Since the use of passwords is the most common type of authentication, certain best practices have to be observed so that attackers will have a hard time to access your account. The use of passphrases,  unique passwords for different accounts, password managers (see LastPass and KeePass), and the use of multi-factor authentication (MFA) (see Google Auth and LastPass Authenticator) are the best practices to build a layered-defense for your passwords.

Updated Systems – From your router to your laptops, mobile devices all the way to the applications, you need to ensure that they are always up-to-date. A lot of successful attacks leverage the exploitation of vulnerable systems, those that are not updated.  You need to enable Automatic Updating.

Backups – Another important practice is to back up your files routinely. The usual expectation of the IT/Security team is that worst-case scenarios will happen such as your workstation will be infected by ransomware or that the device will be lost. Aside from wanting to wipe out the contents of the device, you want to retrieve the information in it. That’s where backups play a vital role.

VPN – In some organizations, confidential company data must remain in the trusted network (company network). But since a lot of employees are working from home, a secured way of getting access to company data stored internally is through a Virtual Private Network (VPN).

Device Misuse – Another important practice is to maintain the use of company-issued devices for work use only. A lot of malware nowadays comes from social networking platforms through third-party ads, hoax, etc.  It is important to remove that risk by not using it for personal use. At the same time, company resources should not be accessed on a personal device. It may be accidentally shared or retained unknowingly.  Lastly, children/relatives/guests should not be allowed to use company-issued devices.

The new normal in the time of pandemic forces business to take drastic and rapid changes in its day-to-day operations. While initially, the move of a lot of organizations is to relax security so that business continuity will not be hindered, it is important that security mechanisms must be restored, reconfigured, and recalibrated so that it will fit the current setup of the organization.

Here is the slide deck on Securing the Organization’s Assets Amidst COVID-19 v1.0. Feel free to use it to help inform more people on how to secure their respective organizations.