# DOM XSS {% hint style="success" %} Learn & practice AWS Hacking:<img src="/.gitbook/assets/arte.png" alt="" data-size="line">[**HackTricks Training AWS Red Team Expert (ARTE)**](https://training.hacktricks.xyz/courses/arte)<img src="/.gitbook/assets/arte.png" alt="" data-size="line">\ Learn & practice GCP Hacking: <img src="/.gitbook/assets/grte.png" alt="" data-size="line">[**HackTricks Training GCP Red Team Expert (GRTE)**<img src="/.gitbook/assets/grte.png" alt="" data-size="line">](https://training.hacktricks.xyz/courses/grte) <details> <summary>Support HackTricks</summary> * Check the [**subscription plans**](https://github.com/sponsors/carlospolop)! * **Join the** 💬 [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** us on **Twitter** 🐦 [**@hacktricks\_live**](https://twitter.com/hacktricks\_live)**.** * **Share hacking tricks by submitting PRs to the** [**HackTricks**](https://github.com/carlospolop/hacktricks) and [**HackTricks Cloud**](https://github.com/carlospolop/hacktricks-cloud) github repos. </details> {% endhint %} ## DOM Vulnerabilities DOM vulnerabilities occur when data from attacker-controlled **sources** (like `location.search`, `document.referrer`, or `document.cookie`) is unsafely transferred to **sinks**. Sinks are functions or objects (e.g., `eval()`, `document.body.innerHTML`) that can execute or render harmful content if given malicious data. * **Sources** are inputs that can be manipulated by attackers, including URLs, cookies, and web messages. * **Sinks** are potentially dangerous endpoints where malicious data can lead to adverse effects, such as script execution. The risk arises when data flows from a source to a sink without proper validation or sanitation, enabling attacks like XSS. {% hint style="info" %} **You can find a more updated list of sources and sinks in** [**https://github.com/wisec/domxsswiki/wiki**](https://github.com/wisec/domxsswiki/wiki) {% endhint %} **Common sources:** ```javascript document.URL document.documentURI document.URLUnencoded document.baseURI location document.cookie document.referrer window.name history.pushState history.replaceState localStorage sessionStorage IndexedDB (mozIndexedDB, webkitIndexedDB, msIndexedDB) Database ``` **Common Sinks:** | [**Open Redirect**](dom-xss.md#open-redirect) | [**Javascript Injection**](dom-xss.md#javascript-injection) | [**DOM-data manipulation**](dom-xss.md#dom-data-manipulation) | **jQuery** | | -------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------- | ------------------------------------------------------------- | ---------------------------------------------------------------------- | | `location` | `eval()` | `scriptElement.src` | `add()` | | `location.host` | `Function() constructor` | `scriptElement.text` | `after()` | | `location.hostname` | `setTimeout()` | `scriptElement.textContent` | `append()` | | `location.href` | `setInterval()` | `scriptElement.innerText` | `animate()` | | `location.pathname` | `setImmediate()` | `someDOMElement.setAttribute()` | `insertAfter()` | | `location.search` | `execCommand()` | `someDOMElement.search` | `insertBefore()` | | `location.protocol` | `execScript()` | `someDOMElement.text` | `before()` | | `location.assign()` | `msSetImmediate()` | `someDOMElement.textContent` | `html()` | | `location.replace()` | `range.createContextualFragment()` | `someDOMElement.innerText` | `prepend()` | | `open()` | `crypto.generateCRMFRequest()` | `someDOMElement.outerText` | `replaceAll()` | | `domElem.srcdoc` | **\`\`**[**Local file-path manipulation**](dom-xss.md#local-file-path-manipulation) | `someDOMElement.value` | `replaceWith()` | | `XMLHttpRequest.open()` | `FileReader.readAsArrayBuffer()` | `someDOMElement.name` | `wrap()` | | `XMLHttpRequest.send()` | `FileReader.readAsBinaryString()` | `someDOMElement.target` | `wrapInner()` | | `jQuery.ajax()` | `FileReader.readAsDataURL()` | `someDOMElement.method` | `wrapAll()` | | `$.ajax()` | `FileReader.readAsText()` | `someDOMElement.type` | `has()` | | **\`\`**[**Ajax request manipulation**](dom-xss.md#ajax-request-manipulation) | `FileReader.readAsFile()` | `someDOMElement.backgroundImage` | `constructor()` | | `XMLHttpRequest.setRequestHeader()` | `FileReader.root.getFile()` | `someDOMElement.cssText` | `init()` | | `XMLHttpRequest.open()` | `FileReader.root.getFile()` | `someDOMElement.codebase` | `index()` | | `XMLHttpRequest.send()` | [**Link manipulation**](dom-xss.md#link-manipulation) | `someDOMElement.innerHTML` | `jQuery.parseHTML()` | | `jQuery.globalEval()` | `someDOMElement.href` | `someDOMElement.outerHTML` | `$.parseHTML()` | | `$.globalEval()` | `someDOMElement.src` | `someDOMElement.insertAdjacentHTML` | [**Client-side JSON injection**](dom-xss.md#client-side-sql-injection) | | **\`\`**[**HTML5-storage manipulation**](dom-xss.md#html-5-storage-manipulation) | `someDOMElement.action` | `someDOMElement.onevent` | `JSON.parse()` | | `sessionStorage.setItem()` | [**XPath injection**](dom-xss.md#xpath-injection) | `document.write()` | `jQuery.parseJSON()` | | `localStorage.setItem()` | `document.evaluate()` | `document.writeln()` | `$.parseJSON()` | | **``**[**`Denial of Service`**](dom-xss.md#denial-of-service)**``** | `someDOMElement.evaluate()` | `document.title` | **\`\`**[**Cookie manipulation**](dom-xss.md#cookie-manipulation) | | `requestFileSystem()` | **\`\`**[**Document-domain manipulation**](dom-xss.md#document-domain-manipulation) | `document.implementation.createHTMLDocument()` | `document.cookie` | | `RegExp()` | `document.domain` | `history.pushState()` | [**WebSocket-URL poisoning**](dom-xss.md#websocket-url-poisoning) | | [**Client-Side SQl injection**](dom-xss.md#client-side-sql-injection) | [**Web-message manipulation**](dom-xss.md#web-message-manipulation) | `history.replaceState()` | `WebSocket` | | `executeSql()` | `postMessage()` | \`\` | \`\` | The **`innerHTML`** sink doesn't accept `script` elements on any modern browser, nor will `svg onload` events fire. This means you will need to use alternative elements like `img` or `iframe`. This kind of XSS is probably the **hardest to find**, as you need to look inside the JS code, see if it's **using** any object whose **value you control**, and in that case, see if there is **any way to abuse** it to execute arbitrary JS. ## Tools to find them * [https://github.com/mozilla/eslint-plugin-no-unsanitized](https://github.com/mozilla/eslint-plugin-no-unsanitized) * Browser extension to check every data taht reaches a potential sink: [https://github.com/kevin-mizu/domloggerpp](https://github.com/kevin-mizu/domloggerpp) ## Examples ### Open Redirect From: [https://portswigger.net/web-security/dom-based/open-redirection](https://portswigger.net/web-security/dom-based/open-redirection) **Open redirect vulnerabilities in the DOM** occur when a script writes data, which an attacker can control, into a sink capable of initiating navigation across domains. It's crucial to understand that executing arbitrary code, such as **`javascript:alert(1)`**, is possible if you have control over the start of the URL where the redirection occurs. Sinks: ```javascript location location.host location.hostname location.href location.pathname location.search location.protocol location.assign() location.replace() open() domElem.srcdoc XMLHttpRequest.open() XMLHttpRequest.send() jQuery.ajax() $.ajax() ``` ### Cookie manipulation From: [https://portswigger.net/web-security/dom-based/cookie-manipulation](https://portswigger.net/web-security/dom-based/cookie-manipulation) DOM-based cookie-manipulation vulnerabilities occur when a script incorporates data, which can be controlled by an attacker, into the value of a cookie. This vulnerability can lead to unexpected behavior of the webpage if the cookie is utilized within the site. Additionally, it can be exploited to carry out a session fixation attack if the cookie is involved in tracking user sessions. The primary sink associated with this vulnerability is: Sinks: ```javascript document.cookie ``` ### JavaScript Injection From: [https://portswigger.net/web-security/dom-based/javascript-injection](https://portswigger.net/web-security/dom-based/javascript-injection) DOM-based JavaScript injection vulnerabilities are created when a script runs data, which can be controlled by an attacker, as JavaScript code. Sinks: ```javascript eval() Function() constructor setTimeout() setInterval() setImmediate() execCommand() execScript() msSetImmediate() range.createContextualFragment() crypto.generateCRMFRequest() ``` ### Document-domain manipulation From: [https://portswigger.net/web-security/dom-based/document-domain-manipulation](https://portswigger.net/web-security/dom-based/document-domain-manipulation) **Document-domain manipulation vulnerabilities** occur when a script sets the `document.domain` property using data that an attacker can control. The `document.domain` property plays a **key role** in the **enforcement** of the **same-origin policy** by browsers. When two pages from different origins set their `document.domain` to the **same value**, they can interact without restrictions. Although browsers impose certain **limits** on the values assignable to `document.domain`, preventing the assignment of completely unrelated values to the actual page origin, exceptions exist. Typically, browsers permit the use of **child** or **parent domains**. Sinks: ```javascript document.domain ``` ### WebSocket-URL poisoning From: [https://portswigger.net/web-security/dom-based/websocket-url-poisoning](https://portswigger.net/web-security/dom-based/websocket-url-poisoning) **WebSocket-URL poisoning** occurs when a script utilizes **controllable data as the target URL** for a WebSocket connection. Sinks: The `WebSocket` constructor can lead to WebSocket-URL poisoning vulnerabilities. ### Link manipulation From: [https://portswigger.net/web-security/dom-based/link-manipulation](https://portswigger.net/web-security/dom-based/link-manipulation) **DOM-based link-manipulation vulnerabilities** arise when a script writes **attacker-controllable data to a navigation target** within the current page, such as a clickable link or the submission URL of a form. Sinks: ```javascript someDOMElement.href someDOMElement.src someDOMElement.action ``` ### Ajax request manipulation From: [https://portswigger.net/web-security/dom-based/ajax-request-header-manipulation](https://portswigger.net/web-security/dom-based/ajax-request-header-manipulation) **Ajax request manipulation vulnerabilities** arise when a script writes **attacker-controllable data into an Ajax request** that is issued using an `XmlHttpRequest` object. Sinks: ```javascript XMLHttpRequest.setRequestHeader() XMLHttpRequest.open() XMLHttpRequest.send() jQuery.globalEval() $.globalEval() ``` ### Local file-path manipulation From: [https://portswigger.net/web-security/dom-based/local-file-path-manipulation](https://portswigger.net/web-security/dom-based/local-file-path-manipulation) **Local file-path manipulation vulnerabilities** arise when a script passes **attacker-controllable data to a file-handling API** as the `filename` parameter. This vulnerability can be exploited by an attacker to construct a URL that, if visited by another user, could lead to the **user's browser opening or writing an arbitrary local file**. Sinks: ```javascript FileReader.readAsArrayBuffer() FileReader.readAsBinaryString() FileReader.readAsDataURL() FileReader.readAsText() FileReader.readAsFile() FileReader.root.getFile() FileReader.root.getFile() ``` ### Client-Side SQl injection From: [https://portswigger.net/web-security/dom-based/client-side-sql-injection](https://portswigger.net/web-security/dom-based/client-side-sql-injection) **Client-side SQL-injection vulnerabilities** occur when a script incorporates **attacker-controllable data into a client-side SQL query in an unsafe way**. Sinks: ```javascript executeSql() ``` ### HTML5-storage manipulation From: [https://portswigger.net/web-security/dom-based/html5-storage-manipulation](https://portswigger.net/web-security/dom-based/html5-storage-manipulation) **HTML5-storage manipulation vulnerabilities** arise when a script **stores attacker-controllable data in the web browser's HTML5 storage** (`localStorage` or `sessionStorage`). While this action is not inherently a security vulnerability, it becomes problematic if the application subsequently **reads the stored data and processes it unsafely**. This could allow an attacker to leverage the storage mechanism to conduct other DOM-based attacks, such as cross-site scripting and JavaScript injection. Sinks: ```javascript sessionStorage.setItem() localStorage.setItem() ``` ### XPath injection From: [https://portswigger.net/web-security/dom-based/client-side-xpath-injection](https://portswigger.net/web-security/dom-based/client-side-xpath-injection) **DOM-based XPath-injection vulnerabilities** occur when a script incorporates **attacker-controllable data into an XPath query**. Sinks: ```javascript document.evaluate() someDOMElement.evaluate() ``` ### Client-side JSON injection From: [https://portswigger.net/web-security/dom-based/client-side-json-injection](https://portswigger.net/web-security/dom-based/client-side-json-injection) **DOM-based JSON-injection vulnerabilities** occur when a script incorporates **attacker-controllable data into a string that is parsed as a JSON data structure and then processed by the application**. Sinks: ```javascript JSON.parse() jQuery.parseJSON() $.parseJSON() ``` ### Web-message manipulation From: [https://portswigger.net/web-security/dom-based/web-message-manipulation](https://portswigger.net/web-security/dom-based/web-message-manipulation) **Web-message vulnerabilities** arise when a script sends **attacker-controllable data as a web message to another document** within the browser. An **example** of vulnerable Web-message manipulation can be found at [PortSwigger's Web Security Academy](https://portswigger.net/web-security/dom-based/controlling-the-web-message-source). Sinks: The `postMessage()` method for sending web messages can lead to vulnerabilities if the event listener for receiving messages handles the incoming data in an unsafe way. ### DOM-data manipulation From: [https://portswigger.net/web-security/dom-based/dom-data-manipulation](https://portswigger.net/web-security/dom-based/dom-data-manipulation) **DOM-data manipulation vulnerabilities** arise when a script writes **attacker-controllable data to a field within the DOM** that is utilized within the visible UI or client-side logic. This vulnerability can be exploited by an attacker to construct a URL that, if visited by another user, can alter the appearance or behaviour of the client-side UI. Sinks: ```javascript scriptElement.src scriptElement.text scriptElement.textContent scriptElement.innerText someDOMElement.setAttribute() someDOMElement.search someDOMElement.text someDOMElement.textContent someDOMElement.innerText someDOMElement.outerText someDOMElement.value someDOMElement.name someDOMElement.target someDOMElement.method someDOMElement.type someDOMElement.backgroundImage someDOMElement.cssText someDOMElement.codebase document.title document.implementation.createHTMLDocument() history.pushState() history.replaceState() ``` ### Denial of Service From: [https://portswigger.net/web-security/dom-based/denial-of-service](https://portswigger.net/web-security/dom-based/denial-of-service) **DOM-based denial-of-service vulnerabilities** occur when a script passes **attacker-controllable data unsafely to a problematic platform API**. This includes APIs that, when invoked, can lead the user's computer to consume **excessive amounts of CPU or disk space**. Such vulnerabilities can have significant side effects, such as the browser restricting the website's functionality by rejecting attempts to store data in `localStorage` or terminating busy scripts. Sinks: ```javascript requestFileSystem() RegExp() ``` ## Dom Clobbering {% content-ref url="dom-clobbering.md" %} [dom-clobbering.md](dom-clobbering.md) {% endcontent-ref %} {% hint style="success" %} Learn & practice AWS Hacking:<img src="/.gitbook/assets/arte.png" alt="" data-size="line">[**HackTricks Training AWS Red Team Expert (ARTE)**](https://training.hacktricks.xyz/courses/arte)<img src="/.gitbook/assets/arte.png" alt="" data-size="line">\ Learn & practice GCP Hacking: <img src="/.gitbook/assets/grte.png" alt="" data-size="line">[**HackTricks Training GCP Red Team Expert (GRTE)**<img src="/.gitbook/assets/grte.png" alt="" data-size="line">](https://training.hacktricks.xyz/courses/grte) <details> <summary>Support HackTricks</summary> * Check the [**subscription plans**](https://github.com/sponsors/carlospolop)! * **Join the** 💬 [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** us on **Twitter** 🐦 [**@hacktricks\_live**](https://twitter.com/hacktricks\_live)**.** * **Share hacking tricks by submitting PRs to the** [**HackTricks**](https://github.com/carlospolop/hacktricks) and [**HackTricks Cloud**](https://github.com/carlospolop/hacktricks-cloud) github repos. </details> {% endhint %}