Mobile App Vulnerability Management: A Probability x Impact Risk Matrix Explained
Posted by Tyler Murphy
Vulnerabilities are inevitable in app development, but not all vulnerabilities require the same attention or resources. Security managers and DevSecOps leaders must effectively prioritize identification and remediation of mobile application security and privacy vulnerabilities to efficiently reduce their overall risk profile.
NowSecure has ample mobile app security testing experience and expertise advising customers about mobile app risk management strategies. Part of applying the right level of resources when they are needed entails knowing what security and privacy vulnerabilities need to be fixed and in what order. This guide will explore a risk-based methodology for identifying, assessing and remediating vulnerabilities using a probability x impact risk matrix.
Understanding Risk: Probability x Impact
Risk is the product of two key factors: probability (likelihood of occurrence) and impact (consequence if exploited). If there is a high likelihood of a vulnerability occurring and large impact in the scenario it does, that vulnerability would be of high or even critical risk. If there is high impact but very low probability, then that vulnerability would not warrant as much concern as one with medium in both categories. It is all about balancing out the two sides of the scale.
Understanding the risk enables security analysts, developers and businesses to make data-driven decisions about how to allocate time and resources to vulnerability identification and remediation.
Why Risk-Based Decision-Making Matters
Stakeholders across the software development lifecycle (SDLC) must weigh risk when prioritizing vulnerability management:
- Security analysts focus on exploitable vulnerabilities with tangible consequences.
- Mobile app developers need to allocate their limited time to the most pressing issues.
- Business leaders and CISOs want to maximize financial returns by addressing security risks that could lead to financial, reputational or legal damage, or by saving time and money not addressing vulnerabilities with acceptable levels of risk.
Having a structured, risk-based framework for vulnerability management ensures more consistent, reliable outcomes.
How to Evaluate Probability in Mobile App Vulnerabilities
Probability reflects how likely it is for a vulnerability to be exploited. When assessing probability, weigh the steps or requirements necessary for exploitation in terms of likelihood of occurrence.
- Low Probability: Physical Access Required:- A common scenario in the mobile security world is that a vulnerability requires the attacker to have physical access to the user’s device. This factor alone usually brings a vulnerability down to a low, regardless of its impact. The attacker would have to be a skilled pickpocket or simply in the right place at the right time to gain access to someone’s phone, making exploitation less probable.
- Low Probability: User Interaction:- Another requirement commonly seen is that a vulnerability requires manual user interaction. For example, the user needs to join a malicious Wi-Fi network and accept a suspicious trust prompt to enable an attacker to view their application traffic. This can result in highly impactful outcomes but requires the user to perform several unsafe and unlikely steps prior.
- High Probability: Remote Exploitation:- Vulnerabilities that can be exploited remotely without user interaction are far more likely. For instance, if a mobile app lacks rate limiting and returns different error messages for valid vs invalid usernames, threat actors can brute-force valid accounts with ease.
Risk is the product of two key factors: probability (likelihood of occurrence) and impact (consequence if exploited)
How to Evaluate Impact in Mobile App Vulnerabilities
Impact measures the damage a vulnerability could cause if exploited. Damage can be:
- Financial: An attacker exploits a vulnerability to generate unlimited promotional codes.
- Reputational: Many applications store some form of user personal information that ranges in sensitivity. Users expect their data to be safely and securely stored, especially in the banking and healthcare industries. A data breach that exposes Personally Identifiable Information (PII) can pose huge reputational damage.
- Legal: A company fails to comply with data privacy laws such as Global Data Protection Regulation (GDPR) or Health Insurance Portability and Accountability Act (HIPAA).
An example of a high-impact vulnerability would be a mHealth app that exposes patient records. This could result in severe legal and regulatory penalties for compromising data privacy and cause the company’s stock to tank.
On the other hand, an example of a low-impact vulnerability would be an application that insecurely stores the user’s name within the device filesystem. If an attacker was able to retrieve this information from the device, it would pose hardly any impact at all. It would be better if the user’s name was not stored, but the effort to pinpoint and resolve the problem might not be a worthwhile endeavor for developers to address while they are working on new updates, features and bug fixes with looming deadlines.
Using a Probability x Impact Risk Matrix
After the probability and impact of a vulnerability have been determined, a risk matrix helps to visualize and assess risk.
Steps to Apply the Risk Matrix
- Determine probability: Assess the likelihood of exploitation.
- Determine impact: Evaluate potential consequences.
- Categorize risk: Use the probability x risk matrix to determine the vulnerability’s risk level.
- Take action: Focus resources on addressing high-risk vulnerabilities first.
Following the principles of this risk-based methodology for prioritizing the identification and remediation of vulnerabilities enables mobile app development and security teams to efficiently reduce their overall risk profiles.
Automation Balances Speed and Security
Development teams often face tight deadlines because first to market can make or break a business. Automated mobile application security testing software like NowSecure Platform quickly and easily integrates continuous testing seamlessly into the CI/CD pipeline.
- Automation benefits: Faster identification and resolution of vulnerabilities during development.
- Business impact insights: NowSecure Platform testing provides a “Business Impact” analysis to inform teams about the potential consequences of each vulnerability.
Conclusion
Adopting a risk-based methodology for prioritizing vulnerabilities empowers mobile AppSec managers and DevSecOps leaders to make optimal decisions from a cost-benefit standpoint. Mobile app risk management solutions such as NowSecure Platform and NowSecure Mobile Pen Testing as a Service (PTaaS) help organizations boost efficiency to speed secure delivery. Weighing probability and impact to prioritize vulnerability management and remediation protects businesses and users alike from costly security breaches.
