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Cross-Site Scripting (XSS) Resources

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A curated AppSec resource library covering XSS, SQLi, SSRF, IDOR, RCE, XXE, OSINT, and more.

Cross-Site Scripting (XSS)

Cross-Site Scripting (XSS) attacks are a type of injection in which malicious scripts are injected into otherwise benign and trusted websites. XSS occurs when an attacker uses a web application to send malicious code, generally in the form of a browser-side script, to a different end user.

XSS remains one of the most prevalent web vulnerabilities, appearing in everything from search bars to user profile fields. The three main variants — Reflected, Stored, and DOM-based — each have distinct attack surfaces. Reflected XSS executes via a crafted URL, Stored XSS persists in the application's database and fires for every visitor, and DOM-based XSS exploits client-side JavaScript that unsafely handles user input without any server round-trip.

The impact of XSS extends well beyond simple alert boxes. Attackers leverage it for session hijacking, credential theft, keylogging, phishing overlays, and as a pivot point for deeper exploitation. In bug bounty programs, Stored XSS on authenticated pages consistently pays well because it can be chained into account takeover.

Modern defenses include Content Security Policy (CSP), output encoding, and frameworks that auto-escape by default — but bypasses are discovered regularly, making XSS a constantly evolving attack surface.

This page collects research, bypass techniques, payloads, and real-world writeups covering all forms of cross-site scripting.

From OWASP

Date Added Link Excerpt
2026-06-08 NEW 2026Multiple VMware Stored XSS Flaw Enable Attackers to Inject Malicious Scripts newsVMware products are affected by multiple stored cross-site scripting (XSS) vulnerabilities. These flaws allow attackers to inject and execute malicious scripts within the affected applications. Successful exploitation could lead to various security risks, including session hijacking, data theft, and unauthorized actions on behalf of users. Users are advised to consult VMware's security advisories for specific product and version information and to apply any available patches or workarounds promptly to mitigate these risks. → gbhackers.com
2026-06-08 NEW 2026Multiple VMware Stored XSS Vulnerabilities Allow Attackers to Inject Malicious Scripts newsVMware has addressed several stored cross-site scripting (XSS) vulnerabilities across its products. These flaws could enable attackers to inject malicious scripts into web applications, potentially leading to unauthorized access, data theft, or other harmful actions. The vulnerabilities were found in specific components of VMware's offerings, allowing for persistent script execution. Users are advised to update their VMware products to the latest versions to mitigate these security risks. The provided link offers detailed information on the affected products and the specific CVEs associated with these vulnerabilities. → cybersecuritynews.com
2026-06-08 NEW 2026JavaScript Prototype Pollution Deep Dive : — Reconnaissance, Exploitation & Bug Bounty Guideline advanced RCEThis article provides a deep dive into JavaScript Prototype Pollution vulnerabilities, explaining the underlying prototype chain and its attack vectors. It covers reconnaissance methodologies, exploitation techniques ranging from XSS to Remote Code Execution (RCE), and real-world bug bounty case studies. The guide also delves into advanced exploit chains, tooling, automation, and defense strategies, offering a production-ready Python scanner. The content focuses on understanding and mitigating this complex JavaScript vulnerability. → infosecwriteups.com
2026-06-08 NEW 2026From XSS to RCE (dompdf 0day) intermediate 10 min read RCELibrary for Remote Code Execution (RCE) in dompdf, a popular PHP library used for rendering PDFs from HTML. The vulnerability, identified as a 0-day by Positive Security, allows an attacker to inject CSS that tricks dompdf into caching a malicious font file with a `.php` extension. This file can then be executed remotely by accessing it from the web server. The exploit leverages the `$isRemoteEnabled` setting and the font caching mechanism within dompdf.
2026-06-04 NEW 2026Cisco Webex Meetings Cross-Site Scripting Vulnerability (CVE-2026-20233) newsWriteup of CVE-2026-20233, a cross-site scripting (XSS) vulnerability in Cisco Webex Meetings. The flaw stemmed from insufficient user input validation, allowing an unauthenticated remote attacker to execute arbitrary script code or access sensitive browser information by tricking a user into clicking a malicious link. Cisco has resolved this issue in their cloud-based Webex Meetings service, requiring no customer action. → systemtek.co.uk
2026-06-03 NEW 2026Zero-Click pretalx XSS Flaw Lets Hackers Hijack Conference Organizer Accounts intermediate 2 min readLibrary for detecting stored XSS vulnerabilities, exemplified by CVE-2026-41241 in pretalx, which allows zero-click account hijacking. This flaw, exploitable with low privileges, bypasses Content Security Policies by leveraging chained exploits involving JavaScript payloads disguised as presentation materials and iframe `srcdoc` attributes. A secondary JavaScript-free technique demotes administrators via image tags in submission titles, triggering a superuser-demotion endpoint. Automated AI agents can weaponize this for mass exploitation across numerous conferences. → hackread.com
2026-06-03 NEW 2026https://github.com/Armur-Ai/Pentest-Swarm-AI beginner 6 min read AI ReconLibrary for advanced penetration testing utilizing a real swarm intelligence architecture. It coordinates independent agents via stigmergy and emergence, allowing them to coordinate by writing to and reading from a shared blackboard, rather than through a central planner. This approach enables emergent attack chains and dynamic agent interaction, supporting tools like nmap, sqlmap, Burp, ZAP, and Metasploit, and is compatible with LLMs such as Claude and Llama.
2026-06-03 NEW 2026House committee chair calls on Instructure to testify in Canvas hack news 3 min readWriteup on the Shiny Hunters attack on Instructure's Canvas platform, highlighting cross-site scripting (XSS) vulnerabilities exploited to hijack admin sessions and exfiltrate student data. The incident prompted a US House committee inquiry, emphasizing the continued relevance of foundational security flaws like input validation and output encoding in critical educational technology infrastructure, despite focus on novel AI threats. → scworld.com
2026-05-28 2026CVE-2026-41241: Critical Stored XSS in Pretalx Conference Platform Allows Attackers 100% Talk Acceptance (Patched in 2026.1.0) news 5 min readWriteup of CVE-2026-41241, a critical stored XSS vulnerability in Pretalx versions prior to 2026.1.0, allowing any registered user to compromise organizer accounts and force talk acceptance. Exploitation involves submitting a talk proposal with a crafted XSS payload in fields like title, speaker display name, or email, which executes when an organizer uses the backend search. The vulnerability stems from improper sanitization and unsafe `innerHTML` usage. Immediate upgrade to version 2026.1.0 is recommended. → rescana.com
2026-05-20 2026CVE-2026-42897 Zero-Day Analysis: Microsoft Exchange Server OWA XSS Vulnerability Exploited in the Wild news 5 min readAnalysis of CVE-2026-42897 details a zero-day cross-site scripting (XSS) vulnerability affecting on-premises Microsoft Exchange Server 2016, 2019, and Subscription Edition. Actively exploited in the wild, this flaw in Outlook Web Access (OWA) allows attackers to execute arbitrary JavaScript, leading to session hijacking and credential theft. The analysis covers threat actor TTPs, exploitation evidence, and actionable mitigations like the Exchange Emergency Mitigation Service (EEMS) and the Exchange On-premises Mitigation Tool (EOMT), noting potential side effects such as the loss of OWA Print Calendar functionality. → rescana.com
2026-05-19 2026Microsoft Exchange Zero-Day Under Attack No Patch Available newsMicrosoft Exchange Zero-Day Under Attack, No Patch Available https://ift.tt/HM5e6fY → darkreading.com
2026-05-18 2026Critical Microsoft Exchange Server Vulnerability Actively Exploited in Attacks news 2 min readWriteup detailing CVE-2026-42897, a critical spoofing vulnerability in Microsoft Exchange Server exploited in the wild, impacting on-premises Outlook Web Access. Threat actors leverage this network-based flaw, characterized by improper input neutralization, to execute arbitrary JavaScript by sending specially crafted emails. This affects Exchange Server 2016, 2019, and Subscription Edition, enabling network-level spoofing and session hijacking. Temporary mitigations, including the Exchange Emergency Mitigation Service or manual tool execution, are advised despite minor functional side effects like calendar printing issues and inline image display problems, pending a permanent patch. → cybersecuritynews.com
2026-05-17 2026Unpatched Microsoft Exchange Server vulnerability exploited (CVE-2026-42897) newsMicrosoft Exchange Server is vulnerable to exploitation due to an unpatched security flaw, identified as CVE-2026-42897. Attackers can leverage this vulnerability, impacting systems that have not been updated. This poses a significant risk to organizations using Microsoft Exchange Server. Further details on the exploitation and its potential impact can be found via the provided link. → helpnetsecurity.com
2026-05-15 2026Critical GitLab Vulnerabilities Enables XSS and Unauthenticated DoS Attacks news 2 min readLibrary of emergency security updates for GitLab addresses multiple high-severity flaws including Cross-Site Scripting (XSS) via CVE-2026-7481 and CVE-2026-5297, and unauthenticated Denial-of-Service (DoS) via CVE-2026-1659 and CVE-2025-14870. These vulnerabilities, impacting self-hosted Community Edition and Enterprise Edition servers, allow for session hijacking, code repository manipulation, and disruption of CI/CD pipelines. Administrators must upgrade to versions 18.11.3, 18.10.6, or 18.9.7 to mitigate these risks. → cybersecuritynews.com
2026-05-14 2026GitLab Security Flaw Allows Cross-Site Scripting and Unauthenticated DoS news 2 min readLibrary update addressing 25 vulnerabilities in GitLab CE/EE, including four critical XSS flaws (CVSS 8.7) affecting Analytics, global search, and Duo Agent output, allowing authenticated attackers to hijack sessions. Three severe DoS vulnerabilities (CVSS 7.5) are also patched, enabling unauthenticated attacks via crafted requests to CI/CD, Duo Workflows, or internal APIs to crash servers. Additional fixes include CVE-2026-1322 (GraphQL authorization flaw), CSRF in JiraConnect, and bypasses for package protection rules. → gbhackers.com
2026-05-12 2026Instructure confirms hackers used Canvas flaw to deface portals news 2 min readWriteup on ShinyHunters exploiting cross-site scripting (XSS) vulnerabilities in Instructure's Canvas LMS. Attackers used these flaws to gain authenticated admin sessions, deface login portals with extortion messages, and exfiltrate over 3.6 terabytes of data. The attacks targeted the Free-for-Teacher environment, leading to temporary downtime and account closures. → bleepingcomputer.com
2026-05-11 2026Cisco Identity Services Engine Stored Cross-Site Scripting Vulnerabilities newsWriteup on Cisco Identity Services Engine (ISE) stored cross-site scripting vulnerabilities, CVE-2025-20204 and CVE-2025-20205. These flaws stem from insufficient input validation in the web-based management interface, allowing authenticated attackers to inject malicious script code. Exploitation enables arbitrary script execution within the interface context or access to sensitive browser data, requiring administrative credentials. Cisco has released updates to address these issues. → systemtek.co.uk
2026-05-09 2026Every Old Vulnerability Is Now an AI Vulnerability beginnerThis article argues that as Artificial Intelligence (AI) systems become more integrated, traditional cybersecurity vulnerabilities are now also AI vulnerabilities. Existing exploits and weaknesses in software, hardware, and network infrastructure can be leveraged to target or compromise AI models. This means that the vast landscape of known security flaws presents a significant risk to AI systems, requiring a re-evaluation of security strategies to account for this expanded threat surface. → darkreading.com
2026-05-03 2026Jenkins Patches High-Severity Plugin Flaws Including Path Traversal and Stored XSS news 2 min readLibrary updates address seven Jenkins plugin vulnerabilities, including critical path traversal (CVE-2026-42520 in Credentials Binding Plugin) enabling arbitrary file writes and remote code execution, and two stored XSS flaws (CVE-2026-42523 in GitHub Plugin, CVE-2026-42524 in HTML Publisher Plugin) allowing JavaScript injection. Medium-severity issues in Script Security, Matrix Authorization Strategy, GitHub Branch Source, and Microsoft Entra ID plugins are also patched. → cybersecuritynews.com
2026-05-03 2026'Chaining vulnerabilities is the hallmark of a sophisticated attack': 750000 websites must be patched as Microsoft's popular open source Dotnetnuke CMS hit by an XSS flaw that allows attackers to hijack admin sessions and take over entire web servers news 2 min readLibrary for securing DotNetNuke CMS, addressing CVE-2026-40321, a cross-site scripting (XSS) flaw. This vulnerability allows attackers to upload malicious SVG files, which, when clicked by an authenticated administrator, execute JavaScript, hijack sessions, and enable arbitrary file writes to the server via the `/API/personaBar/ConfigConsole/UpdateConfigFile` endpoint. This enables the creation of ASPX web shells for full server compromise, impacting over 750,000 websites built on the Microsoft-backed platform.
2026-05-01 2026Jenkins Plugin Updates Fix Path Traversal and Stored XSS Bugs news 2 min readLibrary updates for Jenkins address seven vulnerabilities, including critical path traversal (CVE-2026-42520) in the Credentials Binding Plugin, enabling arbitrary file writes and potential RCE. Stored XSS flaws are patched in the GitHub Plugin (CVE-2026-42523) and HTML Publisher Plugin (CVE-2026-42524), allowing script injection. Medium-severity issues like information disclosure via Script Security Plugin (CVE-2026-42519) and unsafe deserialization in Matrix Authorization Strategy Plugin (CVE-2026-42521) are also resolved, alongside unauthorized connection tests in GitHub Branch Source Plugin (CVE-2026-42522) and open redirects in Microsoft Entra ID Plugin (CVE-2026-42525). → gbhackers.com
2026-04-30 2026Jenkins Patches High-Severity Plugin Vulnerability Including Path Traversal and Stored XSS news 2 min readLibrary update patches Jenkins plugins for critical vulnerabilities including CVE-2026-42520 (path traversal leading to RCE in Credentials Binding Plugin), CVE-2026-42523 (stored XSS in GitHub Plugin), and CVE-2026-42524 (stored XSS in HTML Publisher Plugin). Patched versions and mitigation strategies are detailed for these high-severity flaws. → cyberpress.org
2026-04-30 2026dr34mhacks/XSSNow: Find XSS payloads that actually work by filtering them based on real-world constraints instead of blind payload spraying. intermediate 2 min readLibrary of curated XSS payloads, XSSNow aids researchers and bug bounty hunters by providing context-aware, defense-focused, and real-world tested payloads. It categorizes vulnerabilities by injection context, offers specific collections for WAF bypasses and encoding evasions, and suggests payloads optimized for character limitations and filters. The platform also details CSP bypass techniques and browser quirks, encouraging community contributions to its knowledge base of HTML injection, attribute breaking, JavaScript context, CSS injection, and URL parameter attacks.
2026-04-24 2026Over 10000 Zimbra Servers Vulnerable to XSS Attacks newsOver 10,000 Zimbra Servers Vulnerable to XSS Attacks https://ift.tt/UNZfrVk → secnews.gr
2026-04-24 2026Over 10000 Zimbra servers vulnerable to ongoing XSS attacks news 2 min readWriteup of CVE-2025-48700, an ongoing XSS vulnerability impacting over 10,000 Zimbra Collaboration Suite instances. Exploitable by unauthenticated attackers, this flaw allows arbitrary JavaScript execution, enabling sensitive information access. Patched in June 2025, it has been actively abused in the wild, leading to CISA's inclusion in its Known Exploited Vulnerabilities Catalog and an order for Federal Civilian Executive Branch agencies to secure affected servers. Previous Zimbra vulnerabilities have also been exploited by APT28 and Russian Winter Vivern. → bleepingcomputer.com
2026-04-22 2026Mass-Assignment to Stored XSS and CSP Bypass in a Chatbot Platform advancedMass-Assignment to Stored XSS and CSP Bypass in a Chatbot Platform
2026-04-22 2026Full Disclosure: DOM-Based XSS And Failures In Bug Bounty Hunting beginner 8 min readWriteup detailing a DOM-based XSS vulnerability discovered in a bug bounty hunt, where an insecure `eUrl` parameter on a login page allowed for dynamic resource loading from an attacker-controlled server. This flaw, combined with the absence of the HTTPOnly flag on the `ASPSESSIONID` cookie, enabled a one-click account takeover. The writeup emphasizes the importance of input validation, sanitization, allow-listing, CSP, and proper cookie flag implementation to mitigate such risks.
2026-04-22 2026Cross-Site Scripting (XSS) Is Surging: 4 New CVEs This Week news 1 min readWriteup of surging Cross-Site Scripting (XSS) vulnerabilities, detailing four new CVEs including CVE-2026-27243 with a CVSS score of 9.3. It highlights the increasing prevalence of XSS in SaaS environments, the limitations of automated scanners, and the need for regular testing of controls like WAFs and EDRs against current attack patterns, referencing n8n webhooks abused for malware delivery.
2026-04-22 2026CVE-2025-26244: Stored XSS in DeimosC2 Leading to Privilege Escalation news 7 min readWriteup detailing CVE-2025-26244, a stored cross-site scripting vulnerability in CyberOneSecurity's DeimosC2 v1.1.0-Beta. The writeup demonstrates how an attacker can register a malicious agent by reverse-engineering an agent binary to obtain listener details. This allows injection of an XSS payload into the 'graph' endpoint, which executes when a user views the graph. The stolen cookie then enables privilege escalation and unauthorized access to the C2 framework.
2026-04-22 2026CVE-2025-25461: SeedDMS Stored XSS newsWriteup of CVE-2025-25461, a Stored XSS vulnerability in SeedDMS 6.0.29. Exploitable by users with "Add Category" permissions, an attacker can inject XSS payloads into category names, leading to execution when documents associated with that category are viewed. Potential impacts include session hijacking, data exfiltration, phishing, and remote code execution. Mitigation involves sanitizing user input, employing CSP, and proper output encoding.
2026-04-22 2026Finding DOM Polyglot XSS in PayPal the Easy Way intermediate 6 min readLibrary for discovering DOM-based polyglot XSS vulnerabilities. It details a process utilizing Burp Suite's embedded browser and DOM Invader to identify insecure sinks, specifically on PayPal. The library also demonstrates how to bypass Content Security Policy (CSP) by exploiting unintended script gadgets within the PayPal application, including leveraging older versions of Bootstrap and a custom `youtube.js` gadget to execute JavaScript. → portswigger.net
2026-04-22 2026Cisco IOS XE Web Authentication Reflected XSS Advisory newsCisco IOS XE Web Authentication Reflected XSS Advisory
2026-04-22 2026CVE-2025-66412: Angular Stored XSS via SVG Animation and MathML Attributes news 2 min readWriteup of CVE-2025-66412, an Angular Stored XSS vulnerability. The Angular Template Compiler's incomplete security schema allows bypassing sanitization for URL-holding attributes and SVG animation elements. Attackers can inject `javascript:` URLs into attributes like `xlink:href` or by manipulating the `attributeName` in SVG animations, leading to arbitrary code execution, session hijacking, and data exfiltration. Patches are available in Angular versions 19.2.17, 20.3.15, and 21.0.2.
2026-04-22 2026CVE-2025-0133: PAN-OS Reflected XSS in GlobalProtect Gateway news 2 min readWriteup detailing CVE-2025-0133, a reflected XSS vulnerability in Palo Alto Networks PAN-OS GlobalProtect gateway and portal. This flaw allows attackers to execute malicious JavaScript in a user's browser via crafted links, primarily posing a risk of phishing and credential theft, especially when Clientless VPN is enabled. Mitigation involves enabling Threat IDs 510003 and 510004 via Threat Prevention content version 8995, applying Vulnerability Protection profiles to security rules, or disabling Clientless VPN.
2026-04-22 2026Synthesizing XSS Polyglots with Monte Carlo Tree Search (arXiv 2025) advancedSynthesizing XSS Polyglots with Monte Carlo Tree Search (arXiv 2025) → arxiv.org
2026-04-19 2026Bypassing Signature-Based XSS Filters: Modifying HTML intermediate 2 min readTechnique for bypassing signature-based XSS filters by modifying HTML syntax, demonstrating methods to obfuscate payloads. It explores variations in tag casing, insertion of NULL bytes and superfluous characters, use of alternative attribute delimiters like backticks, and HTML encoding within attribute values to evade detection. Examples are provided using DVWA and OWASP's Broken Web Application Project. → portswigger.net
2026-04-19 2026Advanced XSS Filter Bypass Methods Using Payload Splitting advancedAdvanced XSS Filter Bypass Methods Using Payload Splitting
2026-04-19 2026XSS Payload Bypass Technique: A Practical Guide intermediate 1 min readTechnique for bypassing XSS filters demonstrates obfuscation using mixed-case and redundant slashes to trigger `onfocus` events. Mitigation strategies include input sanitization with DOMPurify and implementing Content Security Policy (CSP). The article also provides Linux and Windows commands for auditing logs and scanning directories for vulnerable scripts, along with advanced payload encoding via `burp-decoder` or base64. → undercodetesting.com
2026-04-19 2026Intigriti July 2025 XSS Challenge — Jorian Woltjer beginner 12 min readLibrary for bypassing XSS filters, leveraging DOM clobbering and Mutation XSS techniques. It demonstrates how to exploit HTML parsing quirks, specifically "foster parenting" within table elements and "node flattening," to manipulate the DOM and override critical elements like `chat-messages`. The library also showcases a method to bypass Content Security Policy (CSP) by exploiting a Socket.IO polling endpoint, reflecting input in a way that allows JavaScript execution.
2026-04-17 2026Multiple Cross-Site Scripting (XSS) Vulnerabilities in Mailcow news 7 min readLibrary detailing three XSS vulnerabilities found in Mailcow, including a critical unauthenticated flaw affecting administrator accounts via Autodiscover logs (GHSA-f9xf-vc72-rcgm). Another XSS targets administrators through attachment filenames in the Quarantine feature (GHSA-2xjc-rg88-jvpp), and a Self-XSS in Login History is escalated via Login CSRF (GHSA-jprq-w83q-q62h). All issues have been fixed since version 2026-03b. → aikido.dev
2026-04-16 2026Bypassing DOMPurify with Good Old XML advanced 5 min readWriteup detailing DOMPurify bypasses found by exploiting parsing inconsistencies between XML and HTML for Processing Instructions (`<?...?>`) and CDATA sections (`<![CDATA[...]]>`). The first bypass leveraged the differing interpretation of Processing Instructions, allowing arbitrary `nodeName` injection. A subsequent bypass exploited how HTML parsers handle CDATA sections outside SVG/MathML, treating them as bogus comments ending with `>` instead of `]]>`. These vulnerabilities were addressed by updates to DOMPurify's node filtering.
2026-04-16 2026Exploring the DOMPurify Library: Bypasses and Fixes intermediate 17 min readArticle detailing bypasses and fixes for the DOMPurify library, exploring how client-side HTML sanitizers work. It highlights vulnerabilities arising from inconsistent HTML parsing, namespace manipulations (e.g., SVG and MathML interactions), and deviations in handling nested element limits. Specific techniques like double parsing, the use of `<form>` element restrictions, and mutations exploiting HTML insertion modes and the stack of open elements are discussed, referencing bypasses like the one found in DOMPurify versions <= 3.1.0 by @IcesFont.
2026-04-16 2026Content Security Policy Bypass Techniques Collection intermediate 8 min readCollection of Content Security Policy (CSP) bypass techniques detailing directives like `script-src`, `default-src`, and `frame-ancestors`, and sources such as `'self'`, `'unsafe-inline'`, and `'unsafe-eval'`. This resource analyzes how CSP mitigates content injection like XSS, yet remains vulnerable to bypasses when misconfigured, highlighting the importance of thorough policy evaluation using tools like CSP Evaluator and CSP Validator. It provides practical examples of exploitable CSP configurations leading to script execution.
2026-04-16 2026CSPBypass: Tool to Bypass Content Security Policies intermediate 2 min readTool for bypassing Content Security Policies (CSP) to exploit XSS vulnerabilities, CSPBypass helps ethical hackers find existing bypass gadgets or contribute new ones. It identifies CSP loopholes, often leveraging JSONP endpoints or JavaScript libraries on whitelisted domains, to execute JavaScript despite restrictive policies. The project encourages community contributions of new bypass techniques, with a dataset curated from Common Crawl for identifying commonly whitelisted domains.
2026-04-16 2026PayloadsAllTheThings: XSS Injection Cheat Sheet beginner 11 min readCheatsheet of XSS injection techniques and payloads, covering methodology, proof of concept examples, and common injection vectors like HTML wrappers, PostMessage, blind XSS, and mutated XSS. It details payload strategies for capturing sensitive data such as cookies and access tokens, crafting fake login forms, keylogging, and exploiting DOM-based vulnerabilities. The resource also highlights effective payloads for modern applications, including sandbox domain contexts, and lists tools like XSSStrike, xsser, Dalfox, and XSpear for blind XSS detection.
2026-04-16 2026Advanced XSS Exploitation: Bypassing CSP and DOM Sanitization advancedAdvanced XSS Exploitation: Bypassing CSP and DOM Sanitization
2026-04-16 2026CVE-2025-63418: Weaponizing the Browser Console - DOM-based XSS Deep Dive advancedCVE-2025-63418: Weaponizing the Browser Console - DOM-based XSS Deep Dive
2026-04-16 2026bypassXSS: A Curated Collection of Advanced XSS Bypass Techniques advanced 1 min readCollection of advanced XSS bypass techniques detailing filter types, encoding methods, DOM manipulation, HTML5 abuse, JavaScript context escapes, WAF strategies against Cloudflare and Akamai, framework-specific payloads for AngularJS and React, and CSP misconfigurations. It includes real-world bug bounty case studies and a payload repository for testing tools like DOMPurify and various WAFs.
2026-04-16 2026Cross-Site Scripting (XSS) Practical CTF Guide intermediateCross-Site Scripting (XSS) Practical CTF Guide
2026-04-10 2026Beyond XSS: Mutation XSS Explained beginner 7 min readWriteup detailing mutation XSS (mXSS) techniques that exploit browser HTML parsing inconsistencies to bypass sanitizers like DOMPurify. It explains how malformed HTML within SVG and style tags can be mutated by browsers, leading to unexpected DOM structures that allow arbitrary code execution through attributes. The article references a specific DOMPurify vulnerability fixed in version 2.0.1.

Frequently Asked Questions

What are the three types of XSS?
The three main types are Reflected XSS (payload delivered via a URL and immediately reflected in the response), Stored XSS (payload persisted in the application database and served to other users), and DOM-based XSS (payload executed entirely in the browser via client-side JavaScript without a server round-trip).
How do you prevent cross-site scripting?
Key defenses include output encoding (HTML, JavaScript, URL, and CSS contexts), Content Security Policy (CSP) headers, using frameworks that auto-escape by default (React, Angular), input validation, and the HttpOnly flag on session cookies to limit the impact of successful attacks.
Why is XSS still so common?
XSS persists because web applications have many injection points (URL parameters, form fields, headers, file uploads), developers must encode output correctly for every context, and modern JavaScript frameworks can be bypassed through dangerouslySetInnerHTML, template injection, or prototype pollution.

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