OWASP Top 10 Explained for Beginners The current 2025 list, what actually changed since 2021, and why Google’s first page is still a version behind

What is the OWASP Top 10?

The OWASP Top 10 is a free awareness document that ranks the ten most critical security risks to web applications, published by the Open Worldwide Application Security Project. The current edition is OWASP Top 10:2025, the eighth installment, built from data donated on more than 2.8 million applications and a practitioner survey.

It is deliberately a short list. Ten names are something a development team can hold in its head, which is the entire design goal — OWASP calls it “a standard awareness document for developers and web application security”. Each name is not one bug but a family of related weaknesses, and the 2025 edition groups 248 individual Common Weakness Enumerations (CWEs) under the ten headings.

What does OWASP stand for?

OWASP stands for the Open Worldwide Application Security Project, a non-profit foundation that publishes free application security standards, tools and training material. It was originally the Open Web Application Security Project; the name widened as its scope moved past the browser into APIs, mobile apps, cloud services and software supply chains.

That rename matters more than it looks. OWASP is not only the Top 10 — the same foundation publishes ZAP, the Application Security Verification Standard, the Web Security Testing Guide, the Dependency-Check tool, and separate Top 10 lists for APIs and mobile. When a job description says “OWASP experience”, it almost always means the web Top 10, but you should know the rest exists.

What are the top 10 OWASP vulnerabilities right now?

The ten categories in OWASP Top 10:2025 are 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 holds first place for the second edition running.

Here is the list with the numbers OWASP published alongside it. “Prevalence” is the share of tested applications found to contain at least one CWE from that category; OWASP only published a figure for some categories, and where it did not we have left the cell blank rather than guess.

Source: OWASP Top 10:2025 project site and its Introduction page, read 1 October 2026. CWE counts and prevalence percentages are OWASP’s own published figures.

What changed between the 2021 and 2025 OWASP Top 10?

Two categories are new or expanded, one was consolidated away, and two were renamed. Software Supply Chain Failures replaces and widens Vulnerable and Outdated Components; Mishandling of Exceptional Conditions is brand new with 24 CWEs; Server-Side Request Forgery was rolled into Broken Access Control; and Security Misconfiguration climbed from fifth to second.

The two that trip people up are the disappearances. If you learned the 2021 list, you learned that SSRF was A10 and that outdated components were A06. Ask about either by that name in an interview in late 2026 and you have dated yourself. SSRF now lives inside Broken Access Control, which is logically where it always belonged — it is the server being made to fetch something it should not be allowed to reach.

Software Supply Chain Failures is the more interesting change. It is not just “old libraries” any more. OWASP describes it as covering compromises occurring within or across the entire ecosystem of software dependencies, build systems and distribution infrastructure. That means a poisoned build pipeline, a hijacked package registry account or a tampered artefact all land in A03 now, and the category was, in OWASP’s words, overwhelmingly voted a top concern in the community survey.

What does each OWASP Top 10 category actually mean?

Each category is a family of related weaknesses, not a single bug: 248 individual CWEs sit inside the ten names, an average of 25 per category. Read them as root causes. Injection covers everything from reflected cross-site scripting to SQL injection, and Broken Access Control alone covers 40 separate CWEs.

Here is each one in the plainest language we can manage, with the kind of thing you would actually find in a test.

A01:2025 — Broken Access Control

The application checks who you are but not what you are allowed to touch. You change /invoice/1042 to /invoice/1041 and read someone else’s invoice. Or a normal user calls an admin endpoint directly because the only thing hiding it was the menu. Forty CWEs, 3.73% of tested applications, and SSRF now sits here too.

A02:2025 — Security Misconfiguration

The code is fine; the settings are not. A default admin password left in place, a verbose error page printing stack traces, an S3 bucket set to public, directory listing enabled, a sample application still deployed. OWASP notes it rose because more and more application behaviour is now decided by configuration rather than code — which is exactly why it moved to number two.

A03:2025 — Software Supply Chain Failures

You wrote secure code and shipped someone else’s problem. A dependency with a known flaw, a package pulled from a registry account that was taken over, a build server an attacker could write to. Only five CWEs and limited data, but OWASP records that this category carries the highest average exploit and impact scores of any in the list.

A04:2025 — Cryptographic Failures

Sensitive data is not protected properly in transit or at rest. Passwords stored with a fast hash or none at all, a site still accepting plain HTTP, card data in a log file, a home-made encryption routine. Thirty-two CWEs and the highest prevalence figure in the 2025 data at 3.80% of applications.

A05:2025 — Injection

Untrusted input ends up being interpreted as a command. SQL injection, command injection, template injection, and cross-site scripting all live here. OWASP points out the spread inside this one category: cross-site scripting is high frequency with low impact, SQL injection is lower frequency with high impact. Thirty-eight CWEs, and the greatest number of associated CVEs in the list.

A06:2025 — Insecure Design

Nothing is implemented wrongly; the design itself allows the abuse. A password reset that only asks for a date of birth. A money transfer with no limit and no second check. A voucher code that can be redeemed in parallel. You cannot patch this one — you have to change the flow, which is why threat modelling belongs before coding.

A07:2025 — Authentication Failures

Proving who you are can be bypassed, guessed or stolen. Credential stuffing with no rate limit, session tokens that never expire, a password reset link that stays valid, multi-factor authentication that can be skipped. Thirty-six CWEs. OWASP notes that wider use of standard authentication frameworks appears to be helping, which is why it stayed at seven rather than climbing.

A08:2025 — Software or Data Integrity Failures

The application trusts code or data it has not verified. An auto-update that does not check a signature, a serialised object deserialised straight from user input, a CI step that runs an unverified script. OWASP positions this as the lower-level sibling of A03: the same broken trust boundary, one layer closer to your own code.

A09:2025 — Security Logging & Alerting Failures

Something happened and nobody found out. No log of failed logins, logs with no user or source IP, logs nobody reads, or — the reason for the rename — perfect logs with no alert attached. OWASP puts it bluntly: great logging with no alerting is of minimal value in identifying security incidents. This is the category that turns a one-day breach into a six-month one.

A10:2025 — Mishandling of Exceptional Conditions

The new one. The application behaves badly when something unexpected happens: a check that fails open instead of closed, an error swallowed silently, a logic branch nobody tested, a crash that leaks internal detail. Twenty-four CWEs. Expect this to be the category interviewers use to find out whether you have read the 2025 list.

Why isn’t the most common risk ranked number one?

Cryptographic Failures is the most prevalent category in the 2025 data at 3.80% of applications tested, yet it ranks fourth, while Broken Access Control ranks first on 3.73%. OWASP calls the list data-informed but not blindly data-driven: exploitability and impact scores from CVE data, plus a community survey, shape the final order.

The mechanics are worth knowing because they come up in interviews. OWASP ranked twelve candidate categories from the contributed data, took eight of the ten from that ranking, and let the remaining two be promoted by a survey of practitioners. The reason given is honest: test data only shows what the industry already knows how to test for automatically, and that is always a view of the past.

For exploitability and impact, OWASP pulled CVSS scores from roughly 175,000 CVE-to-CWE records in the National Vulnerability Database, up from about 125,000 in 2021, covering 643 unique CWEs against 241 last time. CVSS v4.0 was deliberately not used, because its scoring algorithm no longer exposes separate exploit and impact figures. So a low-prevalence category with vicious consequences can outrank a common one with mild ones — which is exactly how A03 made number three on five CWEs.

What is the OWASP Top 10 used for, and by whom?

Companies use the OWASP Top 10 as a shared vocabulary: security teams scope penetration tests against it, developers get trained on it, auditors reference it, and job descriptions list it as a required skill. On Naukri, 1,239 Hyderabad vacancies mentioned OWASP on 1 October 2026.

In practice it shows up in four places. In a penetration test scope, as the minimum coverage a client expects. In a report, as the category each finding is filed under. In a secure-development training plan, because ten names are teachable. And in procurement, where a questionnaire asks whether your application has been tested against the OWASP Top 10. None of those four uses require you to have memorised the order.

Is the OWASP Top 10 still relevant?

Yes, as an awareness list, but it was never designed to be a complete test plan, and OWASP says so itself. It covers 248 of the roughly 968 CWEs in MITRE’s dictionary. For actual test coverage, OWASP publishes the Web Security Testing Guide and the Application Security Verification Standard separately.

This is the honest answer that vendor glossary pages tend to skip. A tester who only knows the Top 10 will miss business logic abuse, chained flaws, and anything the data cannot capture yet. The list is the first page of the syllabus, not the syllabus. OWASP’s own Web Security Testing Guide is where the actual test cases live, and it is what a working penetration tester keeps open.

The second honest caveat: the main Top 10 is for web applications. APIs and mobile applications have their own OWASP lists, and treating the web ten as full API coverage is one of the most common beginner errors we see in mock interviews.

Which category is which, and where does each one sit in a syllabus?

Ten names are easy to memorise and hard to use; what a learner needs is what goes wrong, what it looks like in a real request, and which lab exercise teaches it. The explorer below gives all three for each of the ten 2025 categories, mapped to the exact AimNxt module that covers it.

Use it as a self-test. Pick a category, read the plain-English failure, then try to describe the example out loud before you read ours. If you cannot, that is the category to practise next.

Why is Google’s page one still showing the 2021 list?

On 1 October 2026 the top-ranked result for this query still said its list came from the OWASP Top 10 2021 report, and a widely read tutorial site updated on 27 July 2026 still printed Vulnerable and Outdated Components as category six. Freshness is clearly not gating this search result.

There is a clue in the SERP itself. The video carousel in the middle of the page is already on the 2025 list — Google’s own snippet under the first video reads that the OWASP Top 10 for 2025 highlights broken access control, security misconfiguration and software supply chain failures. So Google knows. The text results around it just have not been rewritten, because a glossary page that ranks well is rarely touched.

The practical lesson for you is simple and it applies to every security topic, not just this one: check the primary source. OWASP publishes the list for free at top10.owasp.org, with the methodology and the CWE counts attached. Any guide, course or institute syllabus that cannot tell you which edition it teaches is telling you something.

What OWASP questions come up in interviews?

Interviewers rarely ask you to recite ten names; they ask you to explain one category, give an example, and say how you would test for it. Broken Access Control, SQL injection and cross-site scripting come up most. Knowing the 2025 edition, including that SSRF moved, is itself a differentiator in late 2026.

From the question banks we maintain for mock interviews, the pattern is three deep rather than ten wide. Expect: name a category and explain it in your own words; walk me through finding it in a live application; what is the fix, and what would you write in the report. One listing we read on Naukri the same morning carried the literal skill tag “owasp top 10” and asked for five to nine years, so the depth expected rises fast with experience.

Two traps worth knowing. First, if you say “SSRF is A10” you are quoting 2021. Second, if you are asked about API risks and answer from the web Top 10, that is a visible gap — OWASP keeps a separate API Security Top 10 for exactly that reason. Our 25 VAPT and penetration testing interview questions post covers the follow-up each of these usually gets.

Who gets paid for OWASP skills in Hyderabad?

Naukri listed 1,239 Hyderabad and Secunderabad vacancies mentioning OWASP on 1 October 2026, and 527 of them sat in the Engineering, Software and QA department rather than IT and Information Security. Roughly two in five OWASP-tagged jobs in the city are developer or tester roles, not security roles.

That is the finding we did not expect, and it changes the advice. At the three-year experience filter the split actually inverts: 131 listings in Engineering, Software and QA against 126 in IT and Information Security. In Hyderabad, OWASP Top 10 knowledge is priced as a software engineering skill at least as much as a security one. If you are a developer or a QA engineer reading this, the list is on your side of the fence too.

Source: Naukri.com listing counts and filter facets for Hyderabad and Secunderabad on the keyword “owasp”, read 1 October 2026. Naukri keyword matching is fuzzy — a listing appears if the term matches anywhere in it. These are vacancy counts and market estimates, not guarantees; pay depends on experience, employer and interview performance.

Now the part nobody selling a course will tell you. Of those 1,239 listings, exactly 20 were open to zero years of experience — 1.6% — and seven of those twenty were unpaid internships. One of the twenty was filed under Food, Beverage and Hospitality. Two of the “0 Yrs” listings at the same employer were titled Application Security Architect and Senior Cybersecurity Engineer, which is a data-entry error rather than a fresher opening, and a “0–2 Yrs” network security listing said “Experience: 4+ years” in its own description.

Move the filter to three years and the count goes from 20 to 284, a little over fourteen times. The OWASP Top 10 is not a skill that gets you hired on its own at zero experience in this city. It is a skill that makes you employable in a developer, QA or support seat, and then compounds. The honest fresher route usually runs through a monitoring role — the SOC Analyst L1 & L2 programme is built for that entry point — or a development job where you are the person who understands why the input validation matters.

How do you actually learn the OWASP Top 10?

You learn it by breaking a deliberately vulnerable application, not by reading the list. DVWA and bWAPP exist for exactly this, and Burp Suite is how you see the request you are changing. All three are named in Module 04 of the AimNxt VAPT and Ethical Hacking curriculum, alongside the OWASP Top 10 sub-topic.

The order that works, and the order the curriculum uses, is this. Learn how a request and a response are shaped first — HTTP methods, headers, cookies, where the DOM ends and the server begins. Only then does an injection make sense, because you can see which part of the request you are poisoning. Learners who skip the HTTP step end up pasting payloads and hoping.

After that, take one category at a time and prove it three ways: find it, exploit it safely, and write the finding up with a severity and a fix. The write-up is the part beginners skip and employers care about, which is why report writing is a full module rather than a footnote. Our guide on how to write a penetration testing report covers the structure, and the VAPT tools every pentester should know post covers what to install.

How AimNxt teaches the OWASP Top 10

The OWASP Top 10 is Module 04 of the fifteen-module AimNxt VAPT and Ethical Hacking programme, a four-month course taught at KPHB 5th Phase in Kukatpally, online, or hybrid. Three later modules then take individual categories apart in the lab: Injection in Module 07, Authentication in Module 08, client-side flaws in Module 09.

Module 04 is called Web Technologies & OWASP Top 10, and its five sub-topics are HTTP Protocol Deep Dive, Web Application Architecture, Client-Side Technologies (JavaScript, Cookies, DOM), Server-Side Technologies (PHP & Backend Logic) and OWASP Top 10 Security Vulnerabilities, with Burp Suite, DVWA and bWAPP as the hands-on tools. The list comes last in that module, after the protocol work, on purpose.

Module names and sub-topics above are taken verbatim from the AimNxt VAPT & Ethical Hacking curriculum; the category mapping in the third column is our own teaching note, not OWASP’s. The programme issues an AimNxt certificate of completion. EC-Council, CompTIA and Offensive Security are the certification bodies for their own exams; AimNxt is an independent training provider that prepares you for them. Placement support runs through the AimNxt Job Interview Guarantee program, which guarantees interview opportunities through the hiring-partner network — not a job offer, a placement, or any salary.

Learning the OWASP Top 10 in Hyderabad and KPHB

Searching for OWASP Top 10 training in Hyderabad and KPHB on 1 October 2026 returned eight providers that all list the OWASP Top 10 in their syllabus, and not one of them says which edition they teach. That single question is the fastest way to test a course in this city.

The local results we read included a Kukatpally internship programme, a web application security course, a tutor marketplace quoting ₹400 to ₹600 per hour for private tuition, and two institute syllabus pages. Every one of them names the OWASP Top 10. None names 2021 or 2025. If a provider cannot answer which edition their slides use, the slides are probably older than their last website refresh.

Two more questions worth asking any Hyderabad provider, and they are cheap to ask on a free demo. Do students get a vulnerable application to break, or only a demonstration? And is there a module where you write the finding up, or does the course end at the exploit? If you want the web half of this taught in a lab rather than in slides, the AimNxt cyber security course in Hyderabad and the VAPT programme both cover it, with weekday, weekend and fast-track batches for people already working.