Weakness (CWE)
CWE-79: Cross-site Scripting
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
How to prevent it (8 mitigations)
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Architecture and Design
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482].
Examples of libraries and frameworks that make it easier to generate properly encoded output include Microsoft's Anti-XSS library, the OWASP ESAPI Encoding module, and Apache Wicket.
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Implementation, Architecture and Design
Understand the context in which your data will be used and the encoding that will be expected. This is especially important when transmitting data between different components, or when generating outputs that can contain multiple encodings at the same time, such as web pages or multi-part mail messages. Study all expected communication protocols and data representations to determine the required encoding strategies.
For any data that will be output to another web page, especially any data that was received from external inputs, use the appropriate encoding on all non-alphanumeric characters.
Parts of the same output document may require different encodings, which will vary depending on whether the output is in the:
- HTML body
- Element attributes (such as src="XYZ")
- URIs
- JavaScript sections
- Cascading Style Sheets and style property
etc. Note that HTML Entity Encoding is only appropriate for the HTML body.
Consult the XSS Prevention Cheat Sheet [REF-724] for more details on the types of encoding and escaping that are needed.
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Architecture and Design, Implementation
Understand all the potential areas where untrusted inputs can enter your software: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide data to the application. Remember that such inputs may be obtained indirectly through API calls.
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Architecture and Design
For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
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Architecture and Design
If available, use structured mechanisms that automatically enforce the separation between data and code. These mechanisms may be able to provide the relevant quoting, encoding, and validation automatically, instead of relying on the developer to provide this capability at every point where output is generated.
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Implementation
Use and specify an output encoding that can be handled by the downstream component that is reading the output. Common encodings include ISO-8859-1, UTF-7, and UTF-8. When an encoding is not specified, a downstream component may choose a different encoding, either by assuming a default encoding or automatically inferring which encoding is being used, which can be erroneous. When the encodings are inconsistent, the downstream component might treat some character or byte sequences as special, even if they are not special in the original encoding. Attackers might then be able to exploit this discrepancy and conduct injection attacks; they even might be able to bypass protection mechanisms that assume the original encoding is also being used by the downstream component.
The problem of inconsistent output encodings often arises in web pages. If an encoding is not specified in an HTTP header, web browsers often guess about which encoding is being used. This can open up the browser to subtle XSS attacks.
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Implementation
With Struts, write all data from form beans with the bean's filter attribute set to true.
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Implementation
To help mitigate XSS attacks against the user's session cookie, set the session cookie to be HttpOnly. In browsers that support the HttpOnly feature (such as more recent versions of Internet Explorer and Firefox), this attribute can prevent the user's session cookie from being accessible to malicious client-side scripts that use document.cookie. This is not a complete solution, since HttpOnly is not supported by all browsers. More importantly, XmlHttpRequest and other powerful browser technologies provide read access to HTTP headers, including the Set-Cookie header in which the HttpOnly flag is set.
Source: MITRE CWE-79
21,903 results · Clear filters · Feed
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Medium 6.1
WIT SynApps Runtime 1.4.11 Reflected XSS via LINK Parameter
WIT SynApps Runtime through 1.4.11 contains a pre-authentication reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject and execute arbitrary JavaScript by submitting a crafted LINK query parameter to the /System/Session-…
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Medium 6.5
WordPress WP Customer Area plugin <= 8.4.0 - Cross Site Scripting (XSS) vulnerability
Subscriber Cross Site Scripting (XSS) in WP Customer Area <= 8.4.0 versions.
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Medium 6.5
WordPress MultiVendorX plugin <= 5.0.20 - Cross Site Scripting (XSS) vulnerability
Subscriber Cross Site Scripting (XSS) in MultiVendorX <= 5.0.20 versions.
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Medium 6.5
WordPress User Registration plugin <= 5.3.0 - Cross Site Scripting (XSS) vulnerability
Subscriber Cross Site Scripting (XSS) in User Registration <= 5.3.0 versions.
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Medium 6.5
WordPress Ultimate Addons for Elementor - Lite plugin <= 2.9.5 - Cross Site Scripting (XSS) vulnerability
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Brainstorm Force Ultimate Addons for Elementor - Lite header-footer-elementor allows Stored XSS.This issue affects Ultimate Addons for Elementor - Lite: from…
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Medium 6.8
Mythic 3.2.16 through 3.4.0.61 Stored XSS via Agent-Downloaded File Preview
Mythic 3.2.16 through 3.4.0.61 contains a stored cross-site scripting vulnerability that allows attackers controlling target endpoint files to run JavaScript in the Mythic UI origin by planting HTML in .pdf-named files. When an operator downloads the file and…
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Medium 6.1
Axigen Mail Server before 10.6.39 and 10.7.1 Stored XSS via Sender Display Name
Axigen Mail Server WebMail before 10.6.39 and 10.7.1 contains a stored cross-site scripting vulnerability that allows unauthenticated remote attackers to inject script via unescaped sender display names in the conversation view. Attackers can send an email wi…
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Medium 6.4
GeoDirectory <= 2.8.199 - Authenticated (Subscriber+) Stored Cross-Site Scripting via 'post_content' Parameter
The GeoDirectory – WP Business Directory Plugin and Classified Listings Directory plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the listing description (post_content) in versions up to, and including, 2.8.199 This is due to insufficien…
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Medium 5.4
FV Flowplayer Video Player <= 7.5.55.7212 - Unauthenticated Stored Cross-Site Scripting via 'ad' Shortcode Attribute in Comments
The FV Flowplayer Video Player plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'comment' parameter in all versions up to, and including, 7.5.55.7212 due to insufficient input sanitization and output escaping. This makes it possible f…
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Medium 6.4
Themify Builder <= 7.8.4 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'variations' Repeater Field
The Themify Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'variations' repeater field of Custom Font (tb_cf) posts in versions up to, and including, 7.8.4. This is due to insufficient input sanitization and output escaping …
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Medium 6.4
Redux Framework <= 4.5.15 - Authenticated (Subscriber+) Stored Cross-Site Scripting via multi_media Field and Client-Supplied checkuser_id
The Redux Framework plugin for WordPress is vulnerable to Stored Cross-Site Scripting in all versions up to, and including, 4.5.15 via the multi_media field. This is due to the field's renderer printing the stored value into an href attribute, a hidden input …
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Medium 6.4
FV Flowplayer Video Player <= 7.5.55.7212 - Authenticated (Subscriber+) Stored Cross-Site Scripting via Shortcode Attributes
The FV Flowplayer Video Player plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'fv_player_videos[_fv_player_user_video][]' parameter in all versions up to, and including, 7.5.55.7212 due to insufficient input sanitization and output …
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Medium 4.7
Like Button Rating ♥ LikeBtn <= 2.6.64 - Unauthenticated Stored Cross-Site Scripting via 'Client-IP' Header
The Like Button Rating ♥ LikeBtn plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'HTTP_CLIENT_IP (Client-IP header)' parameter in all versions up to, and including, 2.6.64 due to insufficient input sanitization and output escaping. T…
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Medium 6.4
Meow Gallery <= 5.5.1 - Authenticated (Author+) Stored Cross-Site Scripting via Attachment Alt Text (aria-label attribute)
The Meow Gallery plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Attachment Alt Text (aria-label attribute) in all versions up to, and including, 5.5.1 due to insufficient input sanitization and output escaping. This makes it possible fo…
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Medium 5.4
FV Flowplayer Video Player <= 7.5.55.7212 - Unauthenticated Stored Cross-Site Scripting via 'align' Shortcode Attribute
The FV Flowplayer Video Player plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'comment (shortcode attribute 'align')' parameter in all versions up to, and including, 7.5.55.7212 due to insufficient input sanitization and output esca…
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Medium 6.4
CP Multi View Events Calendar <= 1.4.43 - Authenticated (Subscriber+) Stored Cross-Site Scripting via 'Subject' Parameter
The CP Multi View Events Calendar plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'Subject' parameter in all versions up to, and including, 1.4.43 due to insufficient input sanitization and output escaping. This makes it possible for…
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Medium 5.1
Frappe LMS has Stored XSS in Course Meta
Frappe Learning Management System (LMS) is a learning system that helps users structure their content. Prior to version 2.52.0, an authenticated user with a course editing role can inject malicious JavaScript through meta tag fields in the Course Management m…
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Medium 6.5
WordPress Media Player Addons for Elementor – Media Player widget for WP plugin <= 1.1.10 - Cross Site Scripting (XSS) vulnerability
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in bPlugins Media Player Addons for Elementor – Media Player widget for WP media-player-addons-for-elementor allows Stored XSS.This issue affects Media Player A…
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Medium 5.3
Stored XSS via crafted URLs in HTML ticket content in Request Tracker
RT's automatic link creation for URLs in HTML ticket content does not HTML-escape the URL it places in the link. A URL crafted to break out of the link's address can add a script that runs when the ticket history is displayed, with no further action by the vi…
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Medium 5.3
Stored XSS via related ticket subject on RTIR Split and Create Incident forms
RTIR's ticket creation forms show the subject of the related ticket when splitting a ticket or creating an incident from a report, and they render that subject without HTML escaping. A ticket subject containing script runs it when a user opens either form. RT…
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Medium 5.3
Stored XSS via HTML scrubber rule in RTIR
RTIR extends RT's HTML scrubber to allow an internal link placeholder, and the extension lets through any link that merely contains the placeholder, including links using the executable javascript: scheme. The change applies to the whole RT instance once RTIR…
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Medium 6.5
WordPress The Events Calendar plugin <= 6.18.2 - Cross Site Scripting (XSS) vulnerability
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Liquid Web / StellarWP The Events Calendar the-events-calendar allows Stored XSS.This issue affects The Events Calendar: from n/a through 6.18.2.
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Medium 4.7
Collabora Online: Reflected HTML injection through host_session_id
Collabora Online is a collaborative online office suite based on LibreOffice technology. Prior to 24.04.18 and 25.04.11, the `host_session_id` query/form parameter is substituted into the `cool.html` editor page without HTML encoding, unlike parameters passed…
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Medium 6.5
WordPress The Events Calendar plugin <= 6.18.2 - Cross Site Scripting (XSS) vulnerability
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Liquid Web / StellarWP The Events Calendar the-events-calendar allows Stored XSS.This issue affects The Events Calendar: from n/a through 6.18.2.
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Medium 6.5
WordPress Blocksy Companion plugin <= 2.1.60 - Cross Site Scripting (XSS) vulnerability
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Creative Themes Blocksy Companion blocksy-companion allows Stored XSS.This issue affects Blocksy Companion: from n/a through 2.1.60.
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Medium 6.1
Netsweeper < 4.0.11 / 4.1.5 Reflected XSS via view_server_log.php
Netsweeper before 4.0.11 and 4.1.0 before 4.1.5 contains a reflected cross-site scripting vulnerability in webadmin/reporter/view_server_log.php that allows remote attackers to execute arbitrary JavaScript by injecting malicious code through the log request p…
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Medium 5.1
Stored XSS in Protectel
ARKETEAM Protectel modules PROTECTELMAJ and BDF contain a note editor module vulnerable to Stored XSS. A low privileged attacker can inject arbitrary HTML and JS into notes, which will be rendered/executed when a user visits this module. This issue has been f…
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Medium 5.4
phpMyAdmin through 5.2.3 Stored XSS via Designer Query History Table Name
phpMyAdmin through 5.2.3 contains a stored cross-site scripting vulnerability that allows database users with CREATE privilege to inject script via unescaped table names in DesignerHistory.display(). Attackers can create a table whose name contains HTML marku…
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Medium 6.8
Firelight Lightbox < 2.3.23 - Contributor+ Stored XSS via Lightbox Link 'href' Attribute
The Firelight Lightbox WordPress plugin before 2.3.23 does not escape the URL of links it opens in its Classic lightbox before inserting it into the page as HTML, which could allow users with a role as low as Contributor to perform Stored Cross-Site Scripting…
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Medium 6.8
Joinchat 6.3.2 - 6.4.1 - Author+ Stored XSS via Button Block Message Attribute
The Joinchat WordPress plugin before 6.4.2 does not escape the message of its button block before outputting it in an HTML attribute on the front end, which could allow users with the Author role and above to perform Stored Cross-Site Scripting attacks agains…
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Medium 4.7
WP User Frontend < 4.3.14 - Reflected XSS via 'field_attr' Parameter
The User Frontend WordPress plugin before 4.3.14 does not sanitise and escape some user-supplied values before reflecting them into HTML attributes in a publicly reachable AJAX response, leading to Reflected Cross-Site Scripting. The affected action is gated …
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Medium 6.4
Events Made Easy <= 3.3.1 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'width' Shortcode Attribute
The Events Made Easy plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'width' parameter in all versions up to, and including, 3.3.1 due to insufficient input sanitization and output escaping. This makes it possible for authenticated a…
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Medium 6.4
Cool FormKit Lite <= 2.7.9 - Authenticated (Contributor+) Stored DOM-Based Cross-Site Scripting via Form Field custom_id Parameter
The Cool FormKit Lite – Advanced Form Builder for Elementor plugin for WordPress is vulnerable to Stored DOM-Based Cross-Site Scripting via the '_elementor_data.form_fields[].custom_id' parameter in all versions up to, and including, 2.7.9 due to insufficient…
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Medium 5.4
MathJax: LaTeX for Drupal - Critical - Cross site scripting - SA-CONTRIB-2026-195
Improper Neutralization of Input During Web Page Generation ("Cross-site Scripting") vulnerability in Drupal MathJax: LaTeX for Drupal allows Cross-Site Scripting (XSS). This issue affects MathJax: LaTeX for Drupal versions: from 0.0.0 to 4.1.2.
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Medium 5.4
Leaflet - Moderately critical - Cross site scripting - SA-CONTRIB-2026-204
Improper Neutralization of Input During Web Page Generation ("Cross-site Scripting") vulnerability in Drupal Leaflet allows Stored XSS. This issue affects Leaflet versions: from 0.0.0 to 10.4.13.
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Medium 6.5
Gin Admin Theme - Moderately critical - Cross-site scripting - SA-CONTRIB-2026-219
Improper Neutralization of Input During Web Page Generation ("Cross-site Scripting") vulnerability in Drupal Gin Admin Theme allows Cross-Site Scripting (XSS). This issue affects Gin Admin Theme versions: from 0.0.0 to 4.1.4, from 5.0.0 to 5.0.16.
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Medium 6.5
Drupal core - Moderately critical - Cross-site scripting - SA-CORE-2026-015
Improper Neutralization of Input During Web Page Generation ("Cross-site Scripting") vulnerability in Drupal Drupal core allows Cross-Site Scripting (XSS). This issue affects Drupal core versions: from 8.9.0 to 10.6.19, from 11.0.0 to 11.3.19, from 11.4.0 to …
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Medium 6.5
Drupal core - Moderately critical - Cross-site scripting - SA-CORE-2026-016
Improper Neutralization of Input During Web Page Generation ("Cross-site Scripting") vulnerability in Drupal Drupal core allows Cross-Site Scripting (XSS). This issue affects Drupal core versions: from 10.3.0 to 10.6.19, from 11.0.0 to 11.3.19, from 11.4.0 to…
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Medium 6.5
CSV Field - Moderately critical - Cross site Scripting - SA-CONTRIB-2026-226
Improper Neutralization of Input During Web Page Generation ("Cross-site Scripting") vulnerability in Drupal CSV Field allows Stored XSS. This issue affects CSV Field versions: from 0.0.0 to 2.0.10, from 3.0.0 to 3.0.7.
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Medium 6.5
Swiper formatter - Moderately critical - Cross-site scripting - SA-CONTRIB-2026-228
Improper Neutralization of Input During Web Page Generation ("Cross-site Scripting") vulnerability in Drupal Swiper formatter allows Stored XSS. This issue affects Swiper formatter versions: from 0.0.0 to 2.1.2, from 3.0.1 to 3.1.0.