Insecure Direct Object Reference (IDOR)
Insecure Direct Object Reference (IDOR) is a vulnerability that arises when attackers can access or modify objects by manipulating identifiers used in a web application's URLs or parameters. It occurs due to missing access control checks, which fail to verify whether a user should be allowed to access specific data.
IDOR vulnerabilities are among the most common and impactful bugs found in bug bounty programs. They typically appear in API endpoints that reference database objects by predictable IDs — user profiles, invoices, messages, or files. An attacker simply changes an ID parameter (e.g., /api/users/1234 to /api/users/1235) to access another user's data. The impact ranges from information disclosure to full account takeover, depending on the affected endpoint.
Common patterns include sequential integer IDs in REST APIs, UUID leakage through other endpoints, and GraphQL queries that expose object references without authorization checks. Prevention requires server-side access control on every request — never relying on obscurity of identifiers alone.
This page collects writeups, tutorials, and tools for finding and exploiting IDOR vulnerabilities, from basic parameter tampering to advanced techniques like BOLA (Broken Object Level Authorization) in modern APIs.
From OWASP
| Date Added | Link | Excerpt |
|---|---|---|
| 2026-07-30 2026 | Account Takeover Across Multiple Programs via Featurebase Integration intermediate 2 min read AuthZ Bug Bounty | Writeup detailing an IDOR vulnerability in the Featurebase feedback platform, leading to account takeover (ATO). The issue stems from Featurebase trusting client-controlled identity attributes without validation, allowing attackers to impersonate other users by modifying `userId` in API requests or changing user profiles and obtaining access tokens. The author notes Featurebase's stance that this is a website owner's responsibility to fix, but suggests JWT for securing installations. → infosecwriteups.com |
| 2026-07-29 2026 | Unprotected admin functionality — PortSwigger Access control vulnerabilities Lab 1 beginner 2 min read AuthZ Bug Bounty | Writeup detailing the exploitation of Broken Access Control (BAC-Portswigger-001) in a PortSwigger lab, where an unprotected administrator panel was discoverable via the `robots.txt` file. An unauthenticated attacker can access the `/administrator-panel` endpoint, allowing sensitive actions like deleting user accounts, leading to full application compromise. Remediation involves enforcing authentication, implementing authorization checks, and avoiding reliance on `robots.txt` for security. → infosecwriteups.com |
| 2026-07-29 2026 | How I found an IDOR in Google Classroom on Day 3 of my Hunting? beginner 3 min read API Sec Bug Bounty | Writeup detailing an Insecure Direct Object Reference (IDOR) vulnerability discovered in Google Classroom. The vulnerability stemmed from the `batchexecute` system, an undocumented internal RPC protocol. By manipulating `submission ID` parameters within POST requests to the `batchexecute` endpoint, an attacker could post private comments to any student's assignment submission, bypassing intended authorization controls and making the comment visible to the student and teacher. The writeup also explains how submission IDs were discoverable through traffic analysis. → infosecwriteups.com |
| 2026-07-28 2026 | LetsDefend: SOC169 — Possible IDOR Attack Detected (Walkthrough) intermediate 6 min read API Sec | Walkthrough of an Insecure Direct Object Reference (IDOR) attack detected by LetsDefend's SOC169 alert. The investigation details how an external IP address enumerated user IDs by sending consecutive POST requests to the `/get_user_info/` endpoint, receiving HTTP 200 OK responses with varying sizes, indicating successful unauthorized access to multiple user records. The analysis confirms the attack was a true positive, revealing an application-layer authorization flaw rather than endpoint compromise. → infosecwriteups.com |
| 2026-07-26 2026 | PentesterFlow - AI Tool for Penetration Testers and Bug Hunters to Automate Workflows intermediate | PentesterFlow is an AI-powered tool designed to automate workflows for penetration testers and bug hunters. It aims to streamline various tasks, enhancing efficiency in security assessments. → cybersecuritynews.com |
| 2026-07-23 2026 | Meta Paid $78000 Bounty for Vulnerability Exposing Customer Support Data news 1 min read | Writeup details a critical vulnerability in Meta's customer support infrastructure, resulting in a $78,000 bug bounty for researcher Rony K Roy. The flaw, involving missing authorization, broken access control, and insecure direct object reference (IDOR), could have exposed user conversations, personal information, and allowed for manipulation of support cases within Meta Horizon Managed Solutions. → securityweek.com |
| 2026-07-23 2026 | Critical Meta IDOR Flaw Let Attackers Access Customer Support Cases news | A critical Insecure Direct Object Reference (IDOR) vulnerability was discovered in Meta's customer support system. This flaw allowed unauthorized attackers to access sensitive customer support case details. The vulnerability, if exploited, could have exposed private user information. The discovery highlights a significant security weakness within Meta's platform, potentially impacting user privacy and trust. → cyberpress.org |
| 2026-07-22 2026 | Critical SolarWinds Serv-U Vulnerabilities Allow Remote Code Execution as Root news | Critical vulnerabilities have been discovered in SolarWinds Serv-U software, enabling attackers to achieve remote code execution with root privileges. This means malicious actors could potentially gain complete control of affected systems. The severity of these flaws highlights a significant security risk for organizations using this software. Further details can be found at the provided link. → cyberpress.org |
| 2026-07-18 2026 | The $0 IDOR That Was Worth More Than a $12,500 P1 intermediate 1 min read Bug Bounty | Writeup analyzing Insecure Direct Object Reference (IDOR) vulnerabilities, contrasting a GraphQL alias abuse bug that garnered a $12,500 bounty with an IDOR exposing all user data for over three years that received $0. The analysis highlights how true impact, beyond proof-of-concept screenshots, dictates bug bounty payouts, noting the latter IDOR was triaged as "Informative" and remained exploitable for years. → infosecwriteups.com |
| 2026-07-18 2026 | How I Found a Cross-Student IDOR in Academy LMS That Leaked Correct Quiz Answers intermediate 8 min read AuthZ | Writeup of a Cross-Student IDOR vulnerability in Academy LMS plugin, affecting over 2,000 installations. The vulnerability, discovered by analyzing the plugin's API controllers, allowed any enrolled student to view another student's quiz results and obtain correct answers. This was achieved by exploiting two authorization failures in the `get_student_quiz_attempt_details` endpoint, which incorrectly processed the `user_id` parameter from requests and evaluated access permissions against the target user's context rather than the caller's. → infosecwriteups.com |
| 2026-07-07 2026 | Predicting MongoDB ObjectId() continuously in Rocket.Chat advanced 12 min read | Writeup detailing a vulnerability in Rocket.Chat, #3687142, where unauthenticated users can access any uploaded file by predicting its MongoDB ObjectId(). The article explains how the ObjectId() is composed of a timestamp, machine/process ID, and a counter, allowing attackers to enumerate valid file IDs and bypass authorization checks through the Livechat functionality. → aikido.dev |
| 2026-06-20 2026 | Breaking Down Two Simple Vulnerabilities That Exposed A School’s Admission Records beginner Bug Bounty | Security researchers discovered data-exposure vulnerabilities on a school's website, revealing sensitive admission records containing PII like names, emails, and addresses. The `/print-form.php?app_number=` endpoint was vulnerable to Insecure Direct Object Reference (IDOR), allowing access to records by manipulating application numbers. → infosecwriteups.com |
| 2026-06-19 2026 | Build an IDOR Vulnerability Lab: Why WHERE Clauses Don’t Protect Your API. intermediate API Sec | Last time we covered SQL injection . I promised IDOR was next. Today you are going to see why a WHERE clause alone will not save you. When you learn about backend APIs feeding your frontend, you are r... → infosecwriteups.com |
| 2026-06-19 2026 | “Bug Bounty Bootcamp #47: Account Takeover 101 — How to Steal Everyone’s Account (Legally)” beginner AuthZ | This article, "Bug Bounty Bootcamp #47: Account Takeover 101," explains that hackers don't need advanced skills to achieve account takeovers. Common vulnerabilities like Insecure Direct Object References (IDOR), insecure invite links, or misconfigured "role" fields can be exploited. The piece encourages readers to learn these techniques legally through bug bounty programs. No specific payout amount is mentioned. → infosecwriteups.com |
| 2026-06-12 2026 | Hacking a Fortune 500 Finance Company via Envoy Proxy Misconfiguration intermediate | A security researcher discovered a vulnerability at a Fortune 500 finance company by exploring their websites. While most domains required SSO credentials, a sister website accessible via Google Dorking allowed verified authors to publish articles. This avenue was initially used to understand the company's systems. The content doesn't mention a specific bug bounty payout amount. → infosecwriteups.com |
| 2026-06-11 2026 | Researcher Used AI to Find $500000 Worth of Bugs Across Google's Internal APIs news 4 min read | Writeup detailing how an AI-powered fuzzing pipeline, utilizing Anthropic's Claude and over 3,600 API keys extracted from 60,000 APKs, uncovered vulnerabilities across Google's internal APIs, including IDOR and broken access control. This systematic approach identified significant security flaws in services like Google Voice, AdExchange, YouTube's Content ID API, Widevine DRM, Eldar, PLX/DataHub, and Vertex AI Search, leading to over $500,000 in bug bounty payouts. The research highlights a pattern of exposed internal APIs and missing authorization checks. |
| 2026-05-12 2026 | Max's Bug Bounty: Two Hundred Thirteen Flaws and Twenty-Two Million in Rewards news 1 min read | Analysis of Max's Bug Bounty program reveals over 213 vulnerabilities identified, with Insecure Direct Object Reference (IDOR) being the most prevalent. The program, which has paid out over 21.9 million rubles, highlights the effectiveness of bug bounty initiatives in improving application security. |
| 2026-05-08 2026 | Dark Web Article Contest Offers $10K for Exploit Articles news 3 min read | Contest announcement on the TierOne dark web forum offers $10,000 for exploit articles, covering topics like RCE via deserialization in React/Node.js, command injection, IDOR in SaaS, SSTI, firmware attacks on routers/cameras, and privilege escalation in RouterOS. Submissions require original content on vulnerability exploitation, with prizes awarded for the best technical write-ups on topics including zero-day browser discoveries and AV/EDR bypass techniques. → thecyberexpress.com |
| 2026-04-22 2026 | New Types of Hacking: IDOR Attacks Evolved advanced | New Types of Hacking: IDOR Attacks Evolved |
| 2026-04-22 2026 | Hunting for IDOR and BAC in B2B Apps with Burp Authorize intermediate | Hunting for IDOR and BAC in B2B Apps with Burp Authorize |
| 2026-04-22 2026 | IDOR in the Wild: What CVE-2025-13526 Teaches Security Engineers news 9 min read | Writeup analyzing CVE-2025-13526, an Insecure Direct Object Reference (IDOR) in a WordPress plugin, highlights how attackers can exploit simple parameter manipulation to access unauthorized data. The article details the mechanics of IDOR, linking it to OWASP API1 (Broken Object Level Authorization) and CWE-639, and emphasizes its prevalence due to rapid development, testing biases, and scattered authorization logic, particularly in the API and AI-driven security landscape. Practical fixes involve centralizing authorization checks and verifying ownership of accessed objects. → penligent.ai |
| 2026-04-22 2026 | CVE-2025-14371: TaxoPress IDOR / Object-Level Authorization Bypass news 4 min read | Writeup of CVE-2025-14371 affecting TaxoPress, detailing an object-level authorization bypass allowing authenticated users with Contributor+ roles to add or remove tags on posts they do not own. This IDOR vulnerability manipulates content integrity by altering search relevance, internal navigation, feeds, and SEO, enabling attackers to reshape content discovery and editorial placement without direct post editing capabilities. The flaw in `modules/taxopress-ai/classes/TaxoPressAiAjax.php` fails to perform a per-object permission check (`current_user_can( 'edit_post', $post_id )`). |
| 2026-04-22 2026 | IDOR-Scanner: Burp Suite Extension for Automated IDOR Detection intermediate 3 min read | Extension for Burp Suite that automatically detects Insecure Direct Object Reference (IDOR) vulnerabilities. It passively scans HTTP requests and responses for numeric fields in URL paths, query parameters, JSON, and form data. Actively, it increments these numeric fields, sending modified requests to identify confirmed IDORs by checking for differing response sizes and 200 OK statuses. An option to right-click and scan specific issues is also provided. |
| 2026-04-22 2026 | GraphQL IDOR Vulnerabilities: What They Are and How to Fix beginner 8 min read | Library focusing on preventing Insecure Direct Object References (IDOR) in GraphQL APIs. It details how IDOR vulnerabilities arise from improper validation of object identifiers, allowing unauthorized data access. The resource highlights real-world examples like vulnerabilities in PayPal, Vimeo, and Shopify, and provides practical advice on implementing strong authentication and strict authorization checks within GraphQL resolvers to mitigate these risks. → escape.tech |
| 2026-04-22 2026 | CVE-2025-64431: IDOR in ZITADEL Organization API Allows Cross-Tenant Tampering news | Library for detecting CVE-2025-64431, an Insecure Direct Object Reference (IDOR) vulnerability in ZITADEL's Organization V2Beta API. This flaw allows authenticated administrators in one organization to tamper with data in other organizations. The vulnerability is addressable through GitLab Dependency Scanning, which helps secure the software supply chain by identifying disclosed vulnerabilities in open-source dependencies. → advisories.gitlab.com |
| 2026-04-22 2026 | OpenCTI GraphQL IDOR Allows Workspace Content Deletion news 1 min read | Library for identifying and mitigating vulnerabilities in applications. This entry focuses on a GraphQL IDOR in OpenCTI (GHSA-pr6m-q4g7-342c) affecting its "WorkspacePopoverDeletionMutation." The flaw permits authenticated users to delete other users' workspace content, including dashboards and investigation cases, by bypassing ownership checks, leading to data loss and operational disruption. |
| 2026-04-22 2026 | CVE-2025-2271: IDOR Vulnerability Detail news | CVE-2025-2271: IDOR Vulnerability Detail |
| 2026-04-22 2026 | CVE-2025-1270: IDOR in h6web by Anapi Group news | Library for detecting and mitigating Insecure Direct Object Reference (IDOR) vulnerabilities, exemplified by CVE-2025-1270 in Anapi Group's h6web. This vulnerability allows authenticated attackers to access other users' information and impersonate them by manipulating the “pkrelated” parameter in the “/h6web/ha_datos_hermano.php” endpoint. Exploiting this IDOR can grant attackers elevated privileges for subsequent requests. |
| 2026-04-19 2026 | IDOR Vulnerability Exploitation Guide — RedfoxSec beginner 7 min read | Guide to Insecure Direct Object Reference (IDOR) vulnerabilities, a critical OWASP Top 10 risk. This resource details how IDORs occur when applications trust user-provided object references without proper authorization checks, enabling unauthorized access to sensitive data. It covers common exploitation techniques like incrementing integer IDs, predictable GUIDs, and path traversal with examples using tools like Burp Suite Intruder and `curl`. The guide also discusses horizontal and vertical IDOR, provides a methodology for discovery, and highlights the importance of testing PUT, DELETE, and PATCH requests, along with harvesting object references from API responses. |
| 2026-04-19 2026 | Bykea: IDOR on In-App Hardcoded Zombie — HackerOne intermediate | Bykea: IDOR on In-App Hardcoded Zombie — HackerOne → hackerone.com |
| 2026-04-19 2026 | IDOR Vulnerability — HackerOne Report 2633771 intermediate | IDOR Vulnerability — HackerOne Report 2633771 → hackerone.com |
| 2026-04-19 2026 | Top 235 IDOR Bug Bounty Reports beginner | Top 235 IDOR Bug Bounty Reports |
| 2026-04-17 2026 | From Reset to Takeover: IDOR in Password Recovery Systems intermediate | From Reset to Takeover: IDOR in Password Recovery Systems |
| 2026-04-17 2026 | IDOR on Password Change to Full Account Takeover intermediate | IDOR on Password Change to Full Account Takeover |
| 2026-04-17 2026 | Vulnlab: IDOR Writeup (Ikhlasdansantai) intermediate | Vulnlab: IDOR Writeup (Ikhlasdansantai) |
| 2026-04-17 2026 | Critical IDOR Vulnerability Leads to User Information Disclosure intermediate | Critical IDOR Vulnerability Leads to User Information Disclosure |
| 2026-04-17 2026 | API1:2019 - Broken object level authorization beginner | Library for preventing API1:2019 Broken Object Level Authorization (IDOR) vulnerabilities. It outlines how attackers substitute resource IDs to access unauthorized data, providing examples such as manipulating `/api/shop1/financial_info`. Prevention techniques include implementing user policy checks, avoiding reliance on client-sent IDs, verifying authorization for every request, and utilizing non-guessable IDs like UUIDs. |
| 2026-04-17 2026 | A Beginner's Guide to IDOR Testing Methodology beginner | A Beginner's Guide to IDOR Testing Methodology |
| 2026-04-17 2026 | Maximizing IDOR Detection with Burp Suite's Autorize intermediate 9 min read | Library for Burp Suite's Autorize extension, this resource details how to leverage it for identifying Insecure Direct Object Reference (IDOR) vulnerabilities by automatically testing authorization with low-privileged user session cookies. It explains the extension's functionality, including its enforcement status detection and customizable filters for identifying authorization bypasses, and provides installation and usage instructions with examples against OWASP Juice Shop. |
| 2026-04-17 2026 | Manual and semi-automated testing for IDORs using Burp Suite intermediate 3 min read | Library for semi-automated and manual testing of Insecure Direct Object References (IDORs) using Burp Suite. It details how to leverage the Autorize plugin for automated checks by sending captured requests from different user contexts and offers a manual approach by identifying and manipulating object identifiers within Burp Suite's Repeater tool, referencing PortSwigger labs as an example. |
| 2026-04-17 2026 | Testing for IDORs (PortSwigger Burp docs) beginner 2 min read | Library for testing Insecure Direct Object References (IDORs), a common access control vulnerability where an application directly uses user-supplied input to access objects. This resource guides users through identifying potential IDORs in parameters, forwarding requests to Burp Intruder, configuring a Sniper attack with payload positions, and analyzing responses to confirm unauthorized access, using an example involving a user ID parameter. → portswigger.net |
| 2026-04-17 2026 | IDOR Vulnerability Explained: Why IDOR Persists (Aikido) beginner 9 min read | Library for identifying Insecure Direct Object References (IDORs), a prevalent vulnerability in modern, API-driven applications. This resource details how IDORs manifest in practice, why traditional testing methods and DAST tools often miss them, and the limitations of static analysis in detecting these contextual authorization failures. It highlights that IDORs, also known as Broken Object Level Authorization (BOLA) in APIs, persist due to evolving system design and the assumption of ownership rather than revalidation, leading to potential data breaches and unauthorized modifications. → aikido.dev |
| 2026-04-17 2026 | How I Found a Critical IDOR Leading to Full Account Takeover intermediate | How I Found a Critical IDOR Leading to Full Account Takeover |
| 2026-04-17 2026 | Exploiting IDOR Vulnerabilities: Prevent Account Takeover beginner 2 min read | Analysis of IDOR vulnerabilities demonstrates how attackers exploit Insecure Direct Object Reference flaws, often through manipulating parameters like `UserId` in HTTP requests identified with tools like Burp Suite or cURL, to achieve Account Takeover. Prevention strategies involve robust server-side checks, comparing session data with request parameters, and utilizing unpredictable identifiers such as UUIDs in database schemas. Logging suspicious activity with tools like Fail2Ban further strengthens defenses against these critical OWASP Top 10 threats. → undercodetesting.com |
| 2026-04-17 2026 | A Journey from IDOR to Account Takeover (Payatu) intermediate 1 min read | Writeup detailing an Insecure Direct Object Reference (IDOR) vulnerability leading to account takeover on pyrus.com. The attack exploits a flaw in the email change confirmation process where the UserID parameter can be manipulated to change a victim's email address. Subsequently, by initiating a password reset, the attacker can receive the reset token on their own email, thereby gaining full account control. |
| 2026-04-17 2026 | Tackling IDOR on UUID based objects (PenTester Nepal) intermediate | Tackling IDOR on UUID based objects (PenTester Nepal) |
| 2026-04-17 2026 | How an IDOR Vulnerability Led to User Profile Modification (HackerOne) intermediate 6 min read | Writeup detailing an Insecure Direct Object Reference (IDOR) vulnerability found on mtnmobad.mtnbusiness.com.ng, which allowed remote users to modify account information including phone numbers. The vulnerability arose from the improper validation of account identifiers and exposed user data in HTTP requests and responses. The report highlights how easily identifiable parameters, such as short numerical IDs and email addresses, can be exploited by attackers using automated tools for unauthorized access and account takeover, emphasizing the need for robust access controls and cryptographically strong identifiers. → hackerone.com |
| 2026-04-17 2026 | IDOR: Admin-to-Owner Account Takeover via Password Reset (StudioCMS) intermediate 2 min read | Writeup of an IDOR vulnerability in StudioCMS allowing admin-to-owner account takeover. The POST /studiocms_api/dashboard/create-reset-link endpoint incorrectly allows any authenticated admin to generate a password reset token for any user, including the owner, without role hierarchy validation. This, combined with the POST /studiocms_api/dashboard/reset-password endpoint, enables a complete account takeover of the highest-privileged account in the system. |
| 2026-04-17 2026 | Exploiting UUIDs in Account Takeover: Pentester's Guide intermediate | Exploiting UUIDs in Account Takeover: Pentester's Guide |
| 2026-04-17 2026 | Top 25 IDOR Bug Bounty Reports (Cristian Cornea) intermediate Bug Bounty | Top 25 IDOR Bug Bounty Reports (Cristian Cornea) → corneacristian.medium.com |
| 2026-04-17 2026 | Day 39: IDOR report - How to write a good bounty write-up beginner | Day 39: IDOR report - How to write a good bounty write-up |
| 2026-04-16 2026 | Chamilo LMS IDOR Leads to Admin Privileges (CVE-2026-40291) news 2 min read | Writeup of CVE-2026-40291 details an Insecure Direct Object Modification (IDOR) vulnerability in Chamilo LMS, allowing any authenticated student to escalate privileges to administrator. Exploitation involves a PUT request to the `/api/users/{id}` endpoint, modifying the `roles` field to `["ROLE_ADMIN"]`, bypassing insufficient authorization checks that only verify user ownership of the record. This high-severity flaw affects versions prior to 2.0.0-RC.3 and requires basic API interaction knowledge. The fix is available in Chamilo LMS version 2.0.0-RC.3. → thehackerwire.com |
| 2026-04-16 2026 | IDOR Vulnerabilities Explained: A Researcher's Guide to Authorization Flaws beginner | IDOR Vulnerabilities Explained: A Researcher's Guide to Authorization Flaws |
| 2026-04-16 2026 | From IDOR to Account Takeover (ATO) intermediate | From IDOR to Account Takeover (ATO) |
| 2026-04-16 2026 | IDOR: A Tale of Account Takeover intermediate | IDOR: A Tale of Account Takeover |
| 2026-04-16 2026 | IDOR Vulnerability Detection Through HTTP Traffic Analysis intermediate 20 min read | Analysis of Insecure Direct Object References (IDOR) attacks, which exploit missing server-side permission verification by allowing manipulation of resource identifiers in URLs, POST forms, REST API requests, cookies, and JSON objects. These attacks, ranging from horizontal (accessing data of users at the same privilege level) to vertical (gaining administrator access), are difficult for traditional firewalls and WAFs to detect as they appear as syntactically correct HTTP requests. Effective detection relies on analyzing HTTP traffic for anomalies like sequential enumeration, unusual error rates (401, 403), or atypical ID values, requiring a combination of preventive developer controls and detective security monitoring. |
| 2026-04-16 2026 | Broken Access Control: Advanced IDOR Exploitation advanced 6 min read | Library for advanced exploitation of broken access control vulnerabilities, focusing on Insecure Direct Object References (IDORs). It covers "object-based" IDORs with JSON manipulation, multi-step IDORs hidden behind workflow sequences, second-order IDORs where input indirectly references resources, and "ID-less" IDORs that bypass direct ID references. Techniques explored include wrapping IDs in arrays, object mapping, boolean usage, and various ID manipulation attempts. |
| 2026-04-16 2026 | IDOR Hunting with Burp Suite: A $1,000 Bug Bounty Case Study intermediate 7 min read | Tool for hunting Insecure Direct Object Reference (IDOR) vulnerabilities, focusing on a $1,000 bug bounty case. It details how Burp Suite's Proxy, Repeater, and Intruder features can be used to identify and automate the discovery of IDORs by tampering with object identifiers and analyzing responses. The entry also covers common IDOR scenarios in APIs, including GraphQL and RESTful endpoints, and provides developer-side prevention techniques like server-side authorization checks and the use of indirect or signed references. |
| 2026-04-16 2026 | How to Find IDORs Like a Pro intermediate | How to Find IDORs Like a Pro |
| 2026-04-10 2026 | IDOR - PortSwigger Web Security beginner 2 min read AuthZ | Reference detailing Insecure Direct Object References (IDOR), a common access control vulnerability popularized by OWASP. It explains how applications using user-supplied input directly to access objects, such as database records via `customer_number` parameters or static files by filename, can lead to horizontal or vertical privilege escalation. Examples include accessing other customers' accounts or sensitive chat transcripts. → portswigger.net |
| 2026-04-10 2026 | IDOR - OWASP Foundation beginner 3 min read | Reference detailing Insecure Direct Object Reference (IDOR) vulnerabilities, a class of Broken Access Control (OWASP Top 10 A01:2025). IDOR occurs when applications expose internal object references, like database keys or file names, without verifying user authorization, allowing attackers to access unauthorized resources by modifying these references in URL path parameters, query strings, or request bodies. Prevention strategies include enforcing server-side authorization, using non-sequential identifiers, applying the principle of least privilege, and validating access at the data layer. → owasp.org |
| 2026-04-10 2026 | How-To: Find IDOR Vulnerabilities for Large Bounty Rewards intermediate | How-To: Find IDOR Vulnerabilities for Large Bounty Rewards → bugcrowd.com |
| 2026-04-10 2026 | Bug Bounty Hunting: Insecure Direct Object References beginner | Bug Bounty Hunting: Insecure Direct Object References |
| 2026-04-10 2026 | How I Found Easy IDOR: Bug Bounty Writeup intermediate | How I Found Easy IDOR: Bug Bounty Writeup |
| 2026-04-10 2026 | HackerOne Report: IDOR Allows Viewing news | HackerOne Report: IDOR Allows Viewing → hackerone.com |
| 2026-04-10 2026 | CVE-2025-67274: Broken Access Control BOLA in aangine news AuthZ | CVE-2025-67274: Broken Access Control BOLA in aangine |
| 2026-04-10 2026 | CVE-2026-33312: BOLA in Vikunja Project news 4 min read AuthZ | Writeup detailing CVE-2026-33312, a Broken Object Level Authorization (BOLA) vulnerability in Vikunja versions 0.20.2 through 2.1.x. This flaw allows read-only users to permanently delete project background images by exploiting an incorrect authorization check that reuses a read-focused validation helper function for delete operations. The vulnerability, fixed in version 2.2.0, results in a low-level integrity compromise with a CVSS 4.0 base score of 5.3, impacting the application's aesthetic configuration and exposing broader access control risks. |
| 2026-04-10 2026 | IDOR Prevention Cheat Sheet beginner 2 min read | Cheatsheet detailing Insecure Direct Object Reference (IDOR) prevention techniques. It explains how IDOR vulnerabilities arise from missing access control checks, allowing attackers to manipulate identifiers in URLs or POST bodies to access unauthorized data. The guide recommends implementing server-side access control for every object, using complex identifiers as a secondary defense, and determining the authenticated user from session information rather than exposed parameters. It provides code examples, such as in Ruby on Rails, demonstrating how to securely scope object lookups to the current user's accessible datasets. → cheatsheetseries.owasp.org |
| 2026-04-10 2026 | IDOR Writeup TryHackMe intermediate | IDOR Writeup TryHackMe |
| 2026-04-10 2026 | What is IDOR? Complete Guide beginner 9 min read | Guide to Insecure Direct Object References (IDOR), this document details how broken access control vulnerabilities allow attackers to manipulate direct object references like database keys or query parameters to access unauthorized data. It covers how IDORs work, including URL tampering, body manipulation, and cookie/JSON manipulation, and explains the risks such as data confidentiality breaches and integrity corruption. The guide also discusses detection methods using tools like Burp Suite and OWASP ZAP, and prevention techniques involving robust access control and session management. |
| 2026-04-10 2026 | IDOR - MDN Web Security beginner 4 min read | Reference detailing Insecure Direct Object Reference (IDOR) vulnerabilities. This security weakness arises from insufficient access control, allowing attackers to exploit exposed object identifiers like database keys or file paths. The document explains how attackers can manipulate URLs, hidden form fields, or file references to gain unauthorized access to other users' data. It provides examples of vulnerable Express.js code and demonstrates how to mitigate IDOR by implementing robust server-side authorization checks and using non-guessable identifiers such as UUIDs. |
| 2026-04-10 2026 | Flowise IDOR & Business Logic Flaw (CVE-2025) news 2 min read | Writeup of CVE-2025, detailing an Insecure Direct Object Reference (IDOR) and Business Logic Flaw in Flowise's `/api/v1/loginmethod` endpoint. This critical vulnerability allows unauthenticated or low-privileged users to overwrite SSO configurations for any organization by bypassing ownership validation checks on the `organizationId`. Attackers can achieve account takeover by replacing legitimate OAuth credentials with their own, and even enable enterprise-only features on free-tier accounts. The writeup includes detection methods, an exploit example, and essential patching guidance focusing on input validation and RBAC. → dailycve.com |
| 2026-04-10 2026 | Insecure Direct Object Reference (IDOR) - A Deep Dive advanced 5 min read | Library covering Insecure Direct Object Reference (IDOR) vulnerabilities, detailing exploitation techniques such as ID parameter manipulation, direct request, mass assignment, token prediction, file path traversal, and API endpoint enumeration. It provides code examples for vulnerable and remediated scenarios, highlighting the impact of IDORs and mentioning CVE-2023-4836 in the User Private Files plugin for WordPress. Remediation strategies include implementing proper access control, using indirect references, employing GUIDs, and validating user input. |
| 2026-04-06 2026 | Web Application Security Testing: A Step-by-Step Learning Guide beginner 6 min read | Guide detailing the foundational concepts of web application security testing, including HTTP fundamentals, HTML/JavaScript basics, and proficiency with Burp Suite. It emphasizes a structured approach, covering reconnaissance, application mapping, systematic testing against the OWASP Top 10, exploitation, and reporting. The guide outlines a step-by-step learning progression from understanding HTTP and mastering Burp Suite to systematically practicing OWASP Top 10 vulnerabilities and applying a professional methodology on unguided machines. |
| 2026-04-06 2026 | CVE-2026-33030: Nginx UI Authorization Bypass news 4 min read | Analysis of CVE-2026-33030 reveals an Insecure Direct Object Reference (IDOR) vulnerability in Nginx UI versions 2.3.3 and prior. This flaw allows any authenticated user to bypass authorization controls, enabling unauthorized access, modification, and deletion of other users' resources due to a lack of user ownership verification in resource endpoint queries. The vulnerability stems from the base Model struct missing a user_id field, leading to broken access control, particularly in multi-user environments. → sentinelone.com |
| 2026-04-06 2026 | GraphQL Security: How I Found and Exploited Critical IDOR and Authorization Bypass intermediate GraphQL | GraphQL Security: How I Found and Exploited Critical IDOR and Authorization Bypass → infosecwriteups.com |
| 2026-04-06 2026 | BugQuest 2026: 31 Days of Broken Access Control beginner 7 min read AuthZ | Library of 31 daily posts from BugQuest 2026, detailing broken access control vulnerabilities. This resource covers authentication versus authorization, common authorization models like RBAC, and various discovery and exploitation techniques, including GraphQL introspection, JWT algorithm confusion, IDOR, request method tampering, and HTTP parameter pollution. It provides practical methods for finding BAC flaws in web applications, APIs, and mobile apps, with a focus on real-world scenarios and reporting. → intigriti.com |
| 2026-04-06 2026 | Nginx UI IDOR Allows Cross-User Resource Access intermediate 1 min read | Writeup of CVE-2026-33030, an Insecure Direct Object Reference (IDOR) in Nginx UI versions 2.3.3 and prior. This high-severity vulnerability allows any authenticated user to access, modify, or delete resources belonging to other users due to a missing user_id field in the application's base Model struct. Exploitation requires an authenticated account and involves identifying another user's resource ID to craft requests that bypass authorization controls for complete cross-user resource access. → thehackerwire.com |
| 2026-04-03 2026 | IDOR Attack Guide | Hackviser beginner 7 min read AuthZ | Guide detailing Insecure Direct Object Reference (IDOR) vulnerabilities, explaining how attackers exploit missing authorization checks in applications. It covers manual testing techniques including URL parameter, POST body, HTTP header, cookie, file access, and API endpoint manipulation. The guide also outlines automated discovery methods using Burp Suite and ffuf, and explores attack vectors like numeric and GUID/UUID manipulation, hash-based bypass, parameter pollution, mass assignment, and blind IDOR exploitation. |
| 2026-04-03 2026 | Reddit Bug Bounty: Exploiting an IDOR Vulnerability in Dubsmash's API intermediate 2 min read | Writeup detailing the exploitation of an Insecure Direct Object Reference (IDOR) vulnerability in Dubsmash's UpdateSound GraphQL API. The flaw allowed unauthorized modification of any soundtrack's metadata by bypassing authorization checks on the `uuid` parameter. The writeup outlines the process of capturing requests with Burp Suite, altering the `uuid`, and forwarding the manipulated request to change soundtrack titles, potentially affecting the entire music library. |
| 2026-04-03 2026 | IDOR: The $1 Billion Authorization Bug beginner | IDOR: The $1 Billion Authorization Bug |
| 2026-04-03 2026 | IDOR Vulnerability: Analysis, Impact, Mitigation | Huntress beginner 4 min read | Reference detailing Insecure Direct Object Reference (IDOR) vulnerabilities, an access control flaw where applications use user-supplied input to directly access objects. It explains how attackers manipulate identifiers in URLs, form fields, or API requests to bypass authorization and access unauthorized resources, impacting products across any technology stack. Detection involves DAST and manual code review, while mitigation focuses on avoiding direct object references or implementing strict server-side access control checks. |
| 2026-04-03 2026 | How to Find IDOR Vulnerabilities: The Bug Bounty Hunter's Practical Guide intermediate 5 min read | Guide to finding Insecure Direct Object References (IDOR) in bug bounty hunting, covering common IDOR patterns, including sequential integers, encoded IDs like base64, and MD5 hashes. It emphasizes the necessity of testing with two accounts, explores various IDOR types like read, write, delete, and function-level, and details methods for both manual and automated detection using tools like Burp Suite and ffuf. The guide also provides a framework for reporting IDOR vulnerabilities and suggests practice targets such as DVWA and PortSwigger Web Academy. |
| 2026-04-03 2026 | Insecure Direct Object References (IDOR) | Intigriti Hackademy beginner 3 min read | Walkthrough of Insecure Direct Object Reference (IDOR) vulnerabilities, explaining how attackers bypass authorization by manipulating user-supplied input to directly access sensitive resources like database records or files. This guide details the impact on confidentiality, integrity, and availability, and emphasizes prevention through strict access control checks, referencing OWASP's cheat sheet for further details. → intigriti.com |
| 2026-04-03 2026 | IDOR in 2025: Why Broken Access Control Still Rules the Vulnerability Charts beginner | IDOR in 2025: Why Broken Access Control Still Rules the Vulnerability Charts |
| 2026-04-03 2026 | IDOR: A Complete Guide to Exploiting Advanced IDOR Vulnerabilities | Intigriti intermediate 8 min read | Guide covering Insecure Direct Object Reference (IDOR) vulnerabilities, detailing methods to identify and exploit them, including basic IDORs, parameter pollution, JSON globbing, method-based variations, content-type manipulation, deprecated API versions, static keywords, and unpredictable IDs. → intigriti.com |
| 2026-01-29 2026 | How I Made Burp Suite My IDOR-Finding Robot Butler (And Found 20+ Bugs) 🤖🔍 intermediate Bug Bounty Burp | The content titled "How I Made Burp Suite My IDOR-Finding Robot Butler (And Found 20+ Bugs)" likely discusses utilizing the Burp Suite tool to automate the discovery of Insecure Direct Object Reference (IDOR) vulnerabilities, leading to the identification of over 20 bugs. The author shares their experience and strategies for leveraging Burp Suite effectively in bug hunting. The content may provide insights into the process of using automation tools for security testing and the successful outcomes achieved through this approach. → infosecwriteups.com |
| 2025-08-14 2025 | devanshbatham/Vulnerabilities-Unmasked beginner 14 min read CSRF XSS | Library of simplified explanations for complex security vulnerabilities, including Cross-Site Scripting (XSS), SQL Injection, Cross-Site Request Forgery (CSRF), ClickJacking, Subdomain Takeover, Privilege Escalation, RBAC Vulnerabilities, Server-Side Request Forgery (SSRF), Vulnerable and Outdated Components, Local File Inclusion (LFI), Denial of Service (DOS), Authentication Bypass, Insecure Direct Object Reference (IDOR), 2FA Bypass, and Race Condition Vulnerabilities. Analogies are provided to illustrate concepts like toy boxes, magic notebooks, and playgrounds for educational purposes. |
| 2025-08-14 2025 | ??Roadmap to Cybersecurity in 2022, Full-Read SSRF, IDOR in GraphQL, GCP P beginner SSRF | The content mentions a roadmap to cybersecurity in 2022, focusing on topics like Full-Read SSRF, IDOR in GraphQL, and GCP P. It suggests a plan or guide for enhancing cybersecurity practices in the upcoming year, highlighting specific areas of concern and potential vulnerabilities to address. The content seems to offer insights or strategies related to cybersecurity trends and challenges for the year ahead, including the importance of understanding SSRF, IDOR, and GCP security measures. |
| 2025-08-14 2025 | https://www.aon.com/cyber-solutions/aon_cyber_labs/finding-more-idors-tips-and-tricks/ intermediate 9 min read | Library of tips and techniques for finding Insecure Direct Object References (IDORs). This resource covers object scope, API route pattern discovery using tools like Burp Suite Intruder or FFUF, adding unexpected IDs, replacing parameter names with tools like Paramalyzer, HTTP parameter pollution, and altering HTTP request methods or content types to bypass access controls. |
| 2025-08-14 2025 | Jobert Abma on Twitter: "Hacker tip: when you’re looking for IDORs in a mod intermediate | Jobert Abma shared a hacker tip on Twitter about finding IDORs in a mod. This tweet suggests that Jobert Abma is providing advice or guidance related to hacking techniques, specifically focusing on Insecure Direct Object References (IDORs) within a mod. The content is concise and implies that Jobert Abma may be sharing insights on exploiting security vulnerabilities in software or applications. |
| 2025-08-14 2025 | Inf0rM@tion Disclosure via IDOR - Pratyush Anjan Sarangi - Medium intermediate | The content is titled "Inf0rM@tion Disclosure via IDOR" by Pratyush Anjan Sarangi on Medium. It likely discusses Information Disclosure through Insecure Direct Object References (IDOR) in web applications. This vulnerability allows unauthorized access to sensitive data by manipulating object references. The article may delve into the impact of IDOR on security and ways to prevent such disclosures. |
| 2025-08-14 2025 | HTTP Request Smuggling IDOR - Hipotermia intermediate 3 min read | Writeup detailing HTTP Request Smuggling chained with an IDOR vulnerability. This technique exploits CL.TE desynchronization using Burp's Request Smuggler plugin to inject a smuggled request that targets an endpoint like `/addCard`, allowing the attacker to add data to a victim's account by manipulating the `Transfer-Encoding` and `Content-Length` headers. The analysis demonstrates crafting requests to modify subsequent user requests and ultimately hijack sensitive information retrieval. |
| 2025-08-14 2025 | Stories Of IDOR-Part 2 - InfoSec Write-ups - Medium intermediate | The content seems to be a continuation of a series called "Stories Of IDOR" focusing on cybersecurity write-ups. It is likely published on the Medium platform. The content may delve into stories related to Insecure Direct Object References (IDOR) in the realm of information security. This series could provide insights, analysis, and possibly solutions related to IDOR vulnerabilities. |
| 2025-08-14 2025 | How I could delete Facebook Ask for Recommendations post’s place objects in intermediate | The content discusses how to delete the location tags associated with Facebook Ask for Recommendations posts. It focuses on removing the specific place objects that are linked to these posts. |
| 2025-08-14 2025 | Chains on Chains!! Chaining several IDOR’s into Account Takeover(PART ONE) intermediate | The content appears to discuss chaining multiple Insecure Direct Object References (IDORs) to execute an Account Takeover attack. This process involves exploiting vulnerabilities in the way user permissions are handled to gain unauthorized access to user accounts. The title suggests that this is part one of a series of articles or guides on this topic. |
| 2025-02-27 2025 | GitHub - errorfiathck/IDOR-Forge: IDOR Forge is an advanced and versatile tool designed to detect Insecure Direct Object Reference (IDOR) vulnerabilities in web applications. intermediate 4 min read | Tool for detecting Insecure Direct Object Reference (IDOR) vulnerabilities in web applications. IDOR Forge dynamically generates and tests payloads across various HTTP methods (GET, POST, PUT, DELETE), scans multiple parameters, and supports proxy integration. It includes features like sensitive data detection, rate limiting handling, concurrent scanning for efficiency, and offers both a command-line interface and an interactive GUI. The tool can output results in TXT or CSV formats and tests a wide array of payload types including SQL injection and file path traversal. |
| 2023-09-22 2023 | IDOR - how to predict an identifier? Bug bounty case study intermediate Bug Bounty Talks | The content discusses IDOR (Insecure Direct Object Reference) vulnerability in bug bounty programs, focusing on predicting identifiers to exploit this flaw. The video likely provides a case study demonstrating how this vulnerability can be leveraged for unauthorized access. It is essential for security professionals and bug bounty hunters to understand and address IDOR vulnerabilities to protect systems and data. |
| 2021-12-25 2021 | How I Get $1350 From IDOR Just Less 1 hours intermediate | How I Get $1350 From IDOR Just Less 1 hours |
| 2021-10-04 2021 | 10 Types of Web Vulnerabilities that are Often Missed beginner 16 min read Bug Bounty SQLi SSRF XSS | Library of web vulnerabilities often overlooked by security testers, including HTTP/2 smuggling, XXE via Office Open XML parsers, SSRF via XSS in PDF generators, and XSS via SVG files. This resource delves into obscure bug classes and less common approaches to traditional vulnerabilities, providing insights for bug bounty hunters and security professionals. It references techniques and tools like `http2smugl` and discussions from Defcon presentations. → labs.detectify.com |
| 2021-07-28 2021 | Chaining password reset link poisoning IDOR and information leakage to achieve account takeover at api.redacted.com advanced AuthZ Bug Bounty | A security researcher successfully exploited a vulnerability at api.redacted.com, achieving account takeover. The attack involved chaining together three distinct vulnerabilities: password reset link poisoning, an Insecure Direct Object Reference (IDOR), and information leakage. This combination allowed the attacker to gain unauthorized access to user accounts. |
| 2021-07-19 2021 | Leveraging Burp Suite extension for finding IDOR(Insecure Direct Object Reference). intermediate Burp | This content describes using a Burp Suite extension to discover Insecure Direct Object References (IDORs). IDOR vulnerabilities allow attackers to access unauthorized data by manipulating object references. The extension likely automates or streamlines the process of identifying these weaknesses. No specific bounty payout amount is mentioned in this content. |
| 2021-02-13 2021 | Finding more IDORs – Tips and Tricks | Aon intermediate | The content provides a compilation of helpful tips, tricks, and techniques aimed at uncovering Insecure Direct Object References (IDORs). It offers guidance on how to identify and exploit these vulnerabilities effectively. |
| 2021-01-24 2021 | All About IDOR Attacks beginner | IDOR attacks involve exploiting vulnerabilities in systems that allow attackers to access data they are not authorized to view. Insecure Direct Object References occur when an application exposes internal implementation objects, such as files or database records, to users without proper authentication. Attackers can manipulate parameters to access sensitive information or perform unauthorized actions. Preventing IDOR attacks requires implementing proper access controls, validating user input, and ensuring that sensitive data is not exposed directly. Understanding how IDOR attacks work is crucial for organizations to protect their data and systems from unauthorized access and potential breaches. |
| 2020-01-13 2020 | GraphQL IDOR leads to information disclosure - Eshan Singh - Medium intermediate GraphQL | Eshan Singh, also known as R0X4R, discusses a recent discovery related to GraphQL IDOR (Insecure Direct Object Reference) leading to information disclosure. Singh shares insights and details about this vulnerability in the Medium article. |
Frequently Asked Questions
- What is an IDOR vulnerability?
- IDOR (Insecure Direct Object Reference) is a type of access control vulnerability where an application exposes internal object references — such as database IDs, filenames, or user identifiers — without proper authorization checks. An attacker can manipulate these references to access other users' data.
- How do you find IDOR vulnerabilities?
- To find IDORs, look for predictable identifiers in API endpoints, URL parameters, and request bodies. Change IDs (numeric, UUID, or encoded values) to those belonging to other users and observe whether the application returns unauthorized data. Testing with two accounts simultaneously is the most effective approach.
- What is the difference between IDOR and BOLA?
- BOLA (Broken Object Level Authorization) is the API-specific term for IDOR, used in the OWASP API Security Top 10. Both describe the same core issue: missing authorization checks when accessing objects by reference. BOLA is the preferred term when discussing API security.
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