Welcome to the OWASP Top 10:2021 documentation.

Redirecting to OWASP Top 10:2025...

Previous versions are available at OWASP Top Ten 2021 and OWASP Top 10 2017 (PDF).

October 2, 2025 - Auditors often view an organization’s failure to address the OWASP Top 10 as an indication that it may be falling short on other compliance standards. Conversely, integrating the Top 10 into the software development life cycle (SDLC) demonstrates an organization’s overall commitment to industry best practices for secure development. For the 2021 list, the OWASP added three new categories, made four changes to naming and scoping, and did some consolidation.

A06:2021-Vulnerable and Outdated Components was previously titled Using Components with Known Vulnerabilities and is #2 in the Top 10 community survey, but also had enough data to make the Top 10 via data analysis. This category moves up from #9 in 2017 and is a known issue that we struggle ...

May 27, 2026 - Broken access control vulnerabilities enable attackers to gain access to user accounts, admin panels, databases, servers, sensitive information, business-critical apps, etc., and let unauthorized users perform privileged functions such as ...

December 21, 2024 - OWASP Top 10–2021 Hello everyone, Ready to unlock OWASP Top 10–2021? Let’s start with the fundamentals from TryHackMe. Task: Broken Access Control Websites have pages that are protected from …

January 2, 2024 - OWASP Top Ten is the list of the 10 most common application vulnerabilities. It also shows their risks, impacts, and countermeasures. Updated every three to four years, the latest OWASP vulnerabilities list was released September 24, 2021.

September 23, 2025 - OWASP Top 10–2021 | THM This is a walkthrough of OWASP Top 10–2021 from TryHackMe Task 4 — 1. Broken Access Control (IDOR Challenge) Deploy the machine and go to http://10.201.125.147 — Login …

OWASP Top Ten 2021 · Where we’ve been and where we are · Who We Be · Nathan Larson wrote vulnerable software for two decades before · wandering into an appsec class about 10 years ago and catching the · security bug. His favorite security defect is H. sapiens.

OWASP Top 10 - 2021 is based on data from over 40 organizations · Previous editions include 2017, 2010, 2007 · Is referenced in many standards, such as · 6 · • · MITRE · • · Defense Information Systems Agency (DISA-STIG) • · PCI DSS · • · Federal Trade Commission (FTC) COPYRIGHT ...

TryHackMe is a free online platform for learning cyber security, using hands-on exercises and labs, all through your browser!

June 9, 2023 - TryHackMe OWASP Top 10–2021 Walkthrough This is a write-up for the room OWASPTop 10 on Tryhackme written 2023. This is meant for those that do not have their own virtual machines and want to use …

TryHackMe is a free online platform for learning cyber security, using hands-on exercises and labs, all through your browser!

April 11, 2025 - CVE-2021–2132: In Oracle WebLogic, a deserialization flaw allowed an attacker to exploit an injection vulnerability to execute arbitrary commands.

Scenario #1: A credential recovery workflow might include “questions and answers,” which is prohibited by NIST 800-63b, the OWASP ASVS, and the OWASP Top 10. Questions and answers cannot be trusted as evidence of identity as more than one person can know the answers, which is why they are ...

December 28, 2025 - Compare OWASP Top 10 2021 vs 2025. New threats like supply chain attacks, LLM risks, and SSRF made the list. See what dropped!

Below are the security risks reported in the OWASP Top 10 2021 report: Access control refers a system that controls access to information or functionality. Broken access controls allow attackers to bypass authorization and perform tasks as though they were privileged users such as administrators.

July 29, 2024 - TryHackMe — OWASP Top 10–2021 — Walkthrough Learn about and exploit each of the OWASP Top 10 vulnerabilities; the 10 most critical web security risks. Difficulty: Easy Task 4: Broken Access …

Injection slides down to the third position. 94% of the applications were tested for some form of injection with a max incidence rate of 19%, an average incidence rate of 3%, and 274k occurrences. Notable Common Weakness Enumerations (CWEs) included are CWE-79: Cross-site Scripting, CWE-89: ...