Hacker's Trend Report 2026: The Vulnerabilities Putting Modern Software at Risk

Cybersecurity Trends 2026: What 67 Security Testing Projects Revealed

Cybersecurity headlines often make it feel like the digital world is constantly on fire. Data breaches, phishing campaigns, ransomware, supply chain attacks, and AI-assisted scams.

But what's the concrete real-life experience of a professional cyber security team?

During 2025, we at Prove Expertise conducted 67 security testing projects across web applications, mobile apps, and API interfaces. More than 650 vulnerabilities were identified and fixed before attackers could exploit them.

The findings provide a valuable snapshot of where organizations are succeeding - and where they still need to improve.

The Cyber Threat Landscape

According to the Finnish Transport and Communications Agency (Traficom) Cyber Security Centre, the cyber threat environment remained consistently active throughout 2025.

Some of the most significant trends included:

• Phishing campaigns targeting Microsoft 365 credentials

• Fake online stores and scam campaigns

• Social engineering through email, SMS, phone calls, and even fake Teams support calls

• Continuous discovery of software vulnerabilities

• Increased regulation around IoT and connected devices

• Growing concern around nation-state espionage and advanced persistent threat (APT) groups

The tactics evolve constantly, but one thing remains unchanged: attackers continue to exploit the same core weaknesses in software systems.

Security Testing Results: More Vulnerabilities Than Ever

Our 2025 testing sample included organizations from multiple industries and various stages of software maturity. All testing was performed externally using a black-box approach, simulating real-world attacker behavior.

The results showed a clear increase in reported vulnerabilities compared to the previous year:

• 67 security testing projects

• 657 reported vulnerabilities

• Average findings per project: 9.81

• Median findings per project: 9

• 2024 reported vulnerabilities: 436

One important observation stood out: many organizations are only now beginning to seriously assess the security of older systems that have been trusted for years.

As the presentation described it, cybersecurity testing can resemble visiting the dentist. The longer you wait, the harder it becomes to take the first step.

Why low severity issues might be the biggest problem?

Low-severity issues may appear harmless individually. However, they can often be chained together into more serious attacks. They also signal weaknesses in development practices and security culture.

And in the age of AI, this can become the signal for AI to flag your site or product to an actual hacker: "You should look deeper into this one."

The severity distribution for 2025 looked like this:

• Critical: 12

• High: 171

• Medium: 196

• Low: 278

The Most Common Vulnerability Categories

The findings aligned heavily with the OWASP Top 10 categories. The most common issues involved:

• Broken access control

• Authentication failures

• Injection vulnerabilities

• Insecure design

• Security misconfigurations

Broken access control and injection vulnerabilities were especially prominent among high and critical severity findings.

Server-Side Request Forgery (SSRF) also emerged as an increasingly important issue, particularly in:

• PDF generation systems

• Header handling

• Backend integrations

The root cause behind many SSRF vulnerabilities was surprisingly simple:

Insufficient input validation.

 

The Security Priorities for 2026

Based on the testing results, three focus areas stand out for organizations heading into 2026.

1. Access Control

Organizations must ensure users can only access the data and functionality appropriate for their role - and equally important, cannot access resources belonging to users at the same privilege level.

Authorization logic remains one of the most common and dangerous weaknesses in modern applications.

2. Cross-Site Scripting (XSS)

Applications still struggle with handling user-generated input safely.

Proper sanitization, validation, and output encoding are critical for preventing attackers from injecting malicious scripts into applications.

3. Session Management & Email Bombing

Weak session handling continues to expose applications to account hijacking and abuse.

At the same time, automated email flooding attacks (“email bombing”) are becoming more common and can severely impact both systems and users.

OWASP Top 10 Is Evolving

The upcoming OWASP Top 10 update reflects how the threat landscape is changing.

New categories emphasize:

• Security misconfiguration

• Software supply chain failures

• Mishandling exceptional conditions

These changes highlight a broader shift in cybersecurity thinking. Security is no longer just about preventing direct attacks against your own application code. Organizations must now secure their entire ecosystem, including dependencies, infrastructure, third-party services, and operational processes.

Security Is Better Than Ever — Even If It Doesn’t Feel Like It

Cybersecurity discussions often focus exclusively on failures. But there is another side to the story.

Every vulnerability discovered during testing is a vulnerability that can be fixed before an attacker finds it.

More organizations are investing in penetration testing, secure development, monitoring, and awareness than ever before. Regulations are improving security requirements for connected devices and critical systems. Detection capabilities are better than they were a decade ago.

And the data supports that perspective. Over 600 vulnerabilities were identified and corrected during these testing projects alone.

The work matters.