OWASP Top 10 Vulnerabilities Explained (With Fixes)

Why the OWASP Top 10 Matters

If you build or run web applications, the OWASP Top 10 vulnerabilities are the risks most likely to get you breached. The list represents the consensus of the global application security community on where web apps fail most often.

This guide explains the current list in plain terms (what each risk is, why it matters and how to prevent it) so your team can build and ship more securely.

Attackers do not invent new tricks for every target; they reuse the same handful of weaknesses again and again. That is why a shared, ranked list is so valuable to defenders.

In short: the OWASP Top 10 is a ranked awareness document of the most critical web application security risks, published by the OWASP Foundation. The 2025 edition lists Broken Access Control, Security Misconfiguration, Software Supply Chain Failures, Cryptographic Failures, Injection, Insecure Design, Authentication Failures, Software or Data Integrity Failures, Security Logging and Alerting Failures, and Mishandling of Exceptional Conditions. Broken Access Control stays at number one because it is both widespread and high-impact. The list is an awareness standard, not an exhaustive checklist. Preventing these risks combines secure design, code review, dependency management and regular testing.

What the List Is

It is a ranked awareness standard for web application security, published by OWASP and revised every few years from contributed testing data and community input.

Each entry is a category rather than a single bug, so one category can cover many specific weaknesses. Broken Access Control alone maps to dozens of Common Weakness Enumeration entries.

It is not an exhaustive checklist. The list focuses attention on the risks that matter most, so teams fix the highest-impact issues first. The full OWASP Top 10:2025 is published free.

What changed in 2025

• Software Supply Chain Failures is new at number three, widening the old "vulnerable and outdated components" entry to the whole build and dependency chain.
• Mishandling of Exceptional Conditions is new at number ten, covering unsafe error handling and failing open.
• Security Misconfiguration rose to number two.
• Server-Side Request Forgery was folded into Broken Access Control.
• Logging and monitoring became Security Logging and Alerting Failures.

The Categories That Cause the Most Damage

Broken Access Control leads the list: when users can act outside their intended permissions, they reach data and functions that should be off limits. Changing an order ID in a URL to view someone else's order is the classic example.

Security Misconfiguration comes next. Default settings, verbose errors, unnecessary features and open cloud storage quietly widen the attack surface.

Software Supply Chain Failures reflect how modern applications are built. Most code in a typical application comes from third-party packages and build tooling, and a compromised dependency or pipeline reaches production with your own code.

Cryptographic Failures and Injection remain in the top five. Weak or missing encryption exposes sensitive data, and injection lets attackers send input the application executes as a command or query.

The remaining categories matter too. Insecure Design, Authentication Failures and Integrity Failures appear constantly in real breaches, which is why a good test checks all ten rather than only the headline few.

How to Prevent Them

Prevention starts in design. Secure defaults, least-privilege access, server-side authorisation checks on every request and input validation stop most issues before a line of exploit code is written.

Automate the rest. Dependency and supply chain scanning catches vulnerable or tampered components, and code review plus testing catch logic flaws.

Then verify. Regular penetration testing confirms the fixes hold, because prevention is ultimately proven by testing, not assumed from policy.

Training matters as well. When developers understand how these risks arise, secure choices become the default rather than an afterthought caught late in testing.

How Penetration Testing Finds Them

A penetration test is the practical way to find the OWASP Top 10 vulnerabilities in your own application. Testers actively attempt each category to prove which weaknesses are present and genuinely exploitable.

A good report maps every finding to its OWASP category with reproduction steps, so developers know exactly what to fix and why.

Automated scanners have their place for coverage, but they miss context. Only a human tester can confirm that a suspected flaw is exploitable in your specific application and business logic, and access control flaws in particular rarely show up in scanner output.

How SecureRoot Helps

SecureRoot finds these risks in your own applications through web application penetration testing and API penetration testing within its VAPT services, actively testing each OWASP category to prove what is real.

Every engagement delivers a developer-ready report with reproduction steps, CVSS severity ratings, proof-of-concept evidence and retesting, mapped to the OWASP categories your auditors and customers recognise.

Talk to SecureRoot →

Frequently asked questions

Straight answers, no marketing speak. If you don’t see your question here, just ask at info@secureroot.co or call +91 73071 48874.

What is the OWASP Top 10?

It is a ranked awareness document listing the most critical web application security risks, published free by the OWASP Foundation and revised every few years from testing data contributed by organisations plus a community survey of practitioners. Treat it as a shared vocabulary rather than a specification. Its value is that developers, testers, auditors, procurement teams and customers all recognise the same ten category names, so a finding described as Broken Access Control means the same thing to the engineer fixing it and the buyer reading the report. Each entry is a category and not a single bug, so one line on the list can cover dozens of distinct Common Weakness Enumeration entries. That breadth is deliberate, because it keeps attention on where applications actually fail most often instead of on whichever vulnerability made the news that quarter. Use the list to prioritise, then use a testable standard to define what good enough actually means.

What is the number one OWASP risk in 2025?

Broken Access Control, which has held the top position since 2021 and stayed there in the 2025 edition because it is both widespread and high impact. The category covers any flaw that lets a user act outside the permissions they were granted: reading or editing another customer's record by changing an identifier in a URL, reaching administrative functions through a route the interface never shows, or escalating a role in a request the server trusts without rechecking. In 2025 server-side request forgery was folded into this category, so forcing the server to make requests on an attacker's behalf now sits here too. Access control flaws are the ones automated scanners handle worst, because deciding who should be allowed to see a given record requires understanding your business rules. That is why they surface when a human tester works through real accounts and real roles rather than during a crawl.

What changed in the OWASP Top 10:2025?

Two categories are new. Software Supply Chain Failures enters at number three, widening the older vulnerable and outdated components entry to cover the whole build and dependency chain, and Mishandling of Exceptional Conditions enters at number ten, covering unsafe error handling and applications that fail open. Security Misconfiguration moved up to number two. Server-side request forgery was merged into Broken Access Control, which stays at number one, and logging and monitoring became Security Logging and Alerting Failures. The renames matter more than they look. Moving from monitoring to alerting shifts the question from whether you collect logs to whether anyone is told when something happens. For most teams the practical consequence of this edition is that your software bill of materials, your pipeline permissions and your error paths are now first-class test targets rather than footnotes at the end of an application assessment.

How do you prevent the OWASP Top 10?

Combine secure design with verification, because prevention is proven by testing rather than assumed from policy. Enforce authorisation on the server for every request instead of hiding options in the interface, apply least privilege, use hardened configuration baselines rather than vendor defaults, pin and scan dependencies and build tooling, encrypt sensitive data properly in transit and at rest, validate and parameterise input, handle errors so the application fails closed, and log security events somewhere a human will actually see the alert. Then confirm the controls hold under code review and penetration testing. Training is the multiplier here, because developers who understand how these categories arise write secure code by default instead of waiting for a report to tell them. Sequence the work so design and automated checks catch the repeatable issues cheaply, and reserve manual testing for the logic and authorisation questions that only a person can answer.

Is the OWASP Top 10 a compliance checklist?

No. OWASP publishes it as an awareness document, and treating it as a pass or fail checklist is a common way for a team to end up with a clean report and an exploitable application. Covering the ten categories is a strong baseline and a reasonable way to talk to auditors and customers, but it directs attention rather than stating requirements. A category such as Insecure Design cannot be closed by a scanner result, and nothing on the list describes the business-logic flaws specific to your own workflows: the discount that can be applied twice, the approval step a determined user can skip, the export that returns another tenant's data. For a detailed and testable requirements list, use the OWASP Application Security Verification Standard. Use the Top 10 to prioritise and to communicate, and the Verification Standard to define what finished actually means for your application.

Does a penetration test cover the OWASP Top 10?

A good web application penetration test covers all ten categories and maps every finding back to its category, with reproduction steps, a CVSS severity rating and proof-of-concept evidence, so developers can confirm a fix rather than guess at it. It should also go further than the list, because business-logic flaws, multi-step workflows and tenant isolation are specific to your application and no generic category captures them. Ask two questions before you buy. Is the testing manual and exploit driven, or is it a scanner report retyped, and is a retest included once your team has fixed what was found. SecureRoot tests web applications and APIs manually, includes the retest, and raises critical findings within three hours rather than holding them for the report. Our Web Application Penetration Testing and API Penetration Testing pages set out the scope, and scoping starts with a call of thirty to forty-five minutes.

Related services

Web Application Penetration Testing · API Penetration Testing · VAPT Services

Get tested by certified experts

Talk to SecureRoot →