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
143 results · Clear filters · Feed
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High 7.1CVE-2026-61989 Public exploit
WordPress Easy Property Listings plugin <= 3.5.25 - Cross Site Scripting (XSS) vulnerability
Unauthenticated Cross Site Scripting (XSS) in Easy Property Listings <= 3.5.25 versions.
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High 7.1CVE-2026-115596 Public exploit
WordPress eCommerce Product Catalog plugin <= 3.6.4 - Cross Site Scripting (XSS) vulnerability
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in impleCode eCommerce Product Catalog ecommerce-product-catalog allows Reflected XSS.This issue affects eCommerce Product Catalog: from n/a through 3.6.4.
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High 7.1CVE-2026-112869 Public exploit
WordPress We’re Open! plugin <= 2.6 - Cross Site Scripting (XSS) vulnerability
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Noah Hearle We’re Open! opening-hours allows Reflected XSS.This issue affects We’re Open!: from n/a through 2.6.
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High 7.1CVE-2026-110899 Public exploit
WordPress Ninja Forms plugin <= 3.15.5 - Cross Site Scripting (XSS) vulnerability
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Kevin Stover Ninja Forms ninja-forms allows Stored XSS.This issue affects Ninja Forms: from n/a through 3.15.5.
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High 7.7CVE-2026-91159 Public exploit
Discourse: Stored oEmbed HTML injection via allowed iframe
Discourse is an open-source discussion platform. Prior to 2026.9.0, 2026.8.1, 2026.7.3, and 2026.1.9, oEmbed processing treated an entire attacker-controlled HTML fragment as trusted when the fragment contained an iframe whose source matched the configured al…
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High 8.8CVE-2026-96230 Public exploit
ASP.NET Core Remote Code Execution Vulnerability
Improper neutralization of input during web page generation ('cross-site scripting') in ASP.NET Core allows an unauthorized attacker to execute code over a network.
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High 7.1CVE-2026-94641 Public exploit
WordPress UsersWP plugin <= 1.2.73 - Cross Site Scripting (XSS) vulnerability
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Stiofan UsersWP userswp allows Reflected XSS.This issue affects UsersWP: from n/a through 1.2.73.
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High 7.2CVE-2026-97347 Public exploit
Post Views Stats Counter <= 1.1.7 - Unauthenticated Stored Cross-Site Scripting via User-Agent Header
The Post Views Stats Counter plugin for WordPress is vulnerable to Stored Cross-Site Scripting via User-Agent Header in all versions up to, and including, 1.1.7 due to insufficient input sanitization and output escaping. This makes it possible for unauthentic…
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High 8.1CVE-2026-93659 Public exploit
Concrete CMS Community Store before 2.7.8 Stored XSS
Concrete CMS Community Store before 2.7.8 renders customer-supplied order fields without HTML escaping in checkout and admin views. Unauthenticated attackers can store script payloads in billing name, email, or phone fields that execute in authenticated manag…
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High 7.2CVE-2026-87915 Public exploit
Popup Maker <= 1.24.0 - Unauthenticated Stored Cross-Site Scripting via values[Name] Parameter
The Popup Maker – Boost Sales, Conversions, Optins, Subscribers with the Ultimate WP Popup Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via values[Name] Parameter in all versions up to, and including, 1.24.0 due to insufficient in…
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High 7.1CVE-2026-93485 Public exploit
WordPress Core <= 7.1 - Cross Site Scripting (XSS) vulnerability
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Automattic WordPress wordpress allows DOM-Based XSS.This issue affects WordPress: from n/a through 7.1.
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High 7.3CVE-2026-18116 Public exploit
Concrete CMS 8.3.0 to 9.5.2 is vulnerable to Stored XSS in Calendar Event Name via Workflow Approval Notifications
Concrete CMS 8.3.0 to 9.5.2 stored calendar event names without sanitization and rendered them without HTML escaping in the workflow approval and deletion notifications shown in the dashboard "Waiting For Me" block. A registered user permitted to add events t…
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High 7.1CVE-2022-35499 Public exploit
In Trimble TM4WEB 21.4.0.4, the external bill viewer endpoint is vulnerable to reflected cross-site scripting via injec…
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High 7.1CVE-2026-82221 Public exploit
WordPress RegistrationMagic plugin <= 6.0.9.8 - Cross Site Scripting (XSS) vulnerability
Unauthenticated Cross Site Scripting (XSS) in RegistrationMagic <= 6.0.9.8 versions.
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High 7.5CVE-2026-78071 Public exploit
Joomla Extension - digital-peak.com - Authenticated, privileged stored XSS in DP Calendar 7.0.0-8.19.5, 9.0.0-10.12.0
Joomla Extension - digital-peak.com - Authenticated, privileged stored XSS in DP Calendar 7.0.0-8.19.5, 9.0.0-10.12.0 - Location title is rendered in data attribute without escaping leads to XSS, needs create permission in DPCalendar.
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High 8.6CVE-2026-66917 Public exploit
Joomla Extension - joomgalleryfriends.net - Stored XSS in JoomGallery < 4.4.0
Joomla Extension - joomgalleryfriends.net - Stored XSS in JoomGallery < 4.4.0 - An authenticated, privileged can store an XSS payload in any image causing JS execution in every visitor's browser.
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High 8.6CVE-2026-74252 Public exploit
Joomla Extension - j2commerce.com - Stored XSS in Guest checkout in J2Store 1.0.0-3.3.20, 4.0.0-4.0.20, 4.1.0-4.1.5
Joomla Extension - j2commerce.com - Stored XSS in Guest checkout in J2Store 1.0.0-3.3.20, 4.0.0-4.0.20, 4.1.0-4.1.5 - J2Commerce 4.1.5 is vulnerable to Stored Cross-Site Scripting (XSS) through the guest checkout billing address fields. An unauthenticated att…
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High 8.6CVE-2026-76564 Public exploit
Joomla Extension - phoca.cz - Stored XSS via User-Agent header in Admin Order View in Phoca Cart 5.0.0-6.1.7
Joomla Extension - phoca.cz - Stored XSS via User-Agent header in Admin Order View in Phoca Cart 5.0.0-6.1.7
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High 7.2CVE-2026-19794 Public exploit
WP-Stats <= 2.56 - Unauthenticated Stored Cross-Site Scripting
The WP-Stats plugin for WordPress is vulnerable to Stored Cross-Site Scripting in all versions up to, and including, 2.56 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web …
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High 8.9CVE-2026-57858 Public exploit
Cal.com Cal.diy 6.2.0 Stored XSS via BookingPageTagManager Analytics Tracking ID
Cal.com Cal.diy versions 2.1.1 through 6.2.0 contain a stored cross-site scripting vulnerability in the BookingPageTagManager component that allows authenticated event owners to inject arbitrary JavaScript by supplying a malicious analytics tracking ID withou…
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High 8.9CVE-2026-64638 Public exploit
WordPress is vulnerable to a pre-auth reflected XSS vulnerability on the login screen. Via a specially crafted maliciou…
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High 8.8CVE-2024-39024 Public exploit
In Packetfence 13.2.0, the WebGui interface setting allows authenticated remote code execution.
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High 8.1CVE-2026-48060 Public exploit
Litestar: HTML Injection Through CSRF Token
Litestar is an Asynchronous Server Gateway Interface (ASGI) framework. Prior to version 2.20.0, Litestar instances which use a template engine in conjunction with CSRF protection are vulnerable to HTML Injection which can be escalated to Cross Site Scripting …
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High 7.1CVE-2026-9833 Public exploit
Tag Groups < 2.2.0 - Reflected XSS via 'tag_groups_task' Parameter
The Tag Groups is the Advanced Way to Display Your Taxonomy Terms WordPress plugin before 2.2.0 does not properly escape one of its AJAX parameters before reflecting it in the response body served with an HTML content type, allowing unauthenticated attackers …
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High 8.2CVE-2026-47423 Public exploit
DOMPurify XSS via `selectedcontent` re-clone
DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. In 3.4.4, DOMPurify allowed selectedcontent by default, allowing browsers to re-clone an XSS payload after sanitization so that unsanitized markup inside <selectedcontent> is re…
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High 7.2CVE-2026-54433 Public exploit
In Roundcube Webmail before 1.6.17 and 1.7.x before 1.7.2, there is Stored Cross-Site Scripting (XSS) via a crafted pla…
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High 8.7CVE-2026-57829 Public exploit
Joomla Extension - joomshaper.com - Unauthenticated stored XSS in Helix Ultimate < 2.2.7
Joomla Extension - joomshaper.com - Unauthenticated stored XSS in Helix Ultimate < 2.2.7 - The Joomla extension Helix Ultimate is vulnerable to an unauthenticated stored XSS.
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High 8.8CVE-2026-61876 Public exploit
LuCI DHCPv6 Lease Hostname Stored Cross-Site Scripting
LuCI versions fail to properly encode DHCPv6 lease hostnames before rendering in status tables, allowing adjacent network attackers to inject HTML markup. Attackers can send a DHCPv6 Client FQDN containing script tags that execute in the administrator's brows…
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High 8.1CVE-2026-59795 Public exploit
In JetBrains TeamCity before 2026.1.2 stored XSS via unauthenticated agent registration was possible
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High 8.2CVE-2026-29519 Public exploit
Lucee CFML Server Reflected XSS via URL Path Parsing
Lucee CFML Server versions across the 5.3.x, 6.1.x, 6.2.x, and 7.0.x release lines contain a reflected cross-site scripting vulnerability in URL path parsing that allows unauthenticated remote attackers to execute arbitrary JavaScript in a victim's browser by…
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High 7.1CVE-2026-56011 Public exploit
WordPress MapPress Maps for WordPress plugin <= 2.97.3 - Cross Site Scripting (XSS) vulnerability
Unauthenticated Cross Site Scripting (XSS) in MapPress Maps for WordPress <= 2.97.3 versions.
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High 7.3CVE-2026-9086 Public exploit
Keycloak: keycloak: cross-site scripting (xss) via case-insensitive uri validation bypass
A flaw was found in Keycloak. A remote attacker with administrative privileges, specifically those with `manage-client` permission or access to client registration endpoints, could bypass client Uniform Resource Identifier (URI) validation. This is achieved b…
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High 7.1CVE-2026-40791 Public exploit
WordPress WP Time Slots Booking Form plugin <= 1.2.46 - Cross Site Scripting (XSS) vulnerability
Unauthenticated Cross Site Scripting (XSS) in WP Time Slots Booking Form <= 1.2.46 versions.
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High 7.2CVE-2026-5513 Public exploit
Online Scheduling and Appointment Booking System – Bookly <= 27.2 - Unauthenticated Stored Cross-Site Scripting via 'bookly-customer-full-name' Cookie
The Online Scheduling and Appointment Booking System – Bookly plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'bookly-customer-full-name' cookie in versions up to, and including, 27.2 due to insufficient input sanitization and output…
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High 7.1CVE-2026-49069 Public exploit
WordPress WPZOOM Portfolio plugin <= 1.4.21 - Cross Site Scripting (XSS) vulnerability
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in WPZOOM Portfolio allows Reflected XSS. This issue affects WPZOOM Portfolio: from n/a through 1.4.21.
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High 7.6CVE-2026-9809 Public exploit
Mautic has Stored Cross-Site Scripting (XSS) in Projects Component
A stored Cross-Site Scripting (XSS) vulnerability exists in the Projects component of Mautic 7. When displaying project tags and popovers on administrative detail views (such as campaigns, emails, or forms), user-supplied project names are rendered without pr…
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High 7.2CVE-2025-11262 Public exploit
Link Whisper Free <= 0.9.0 - Unauthenticated Stored Cross-Site Scripting
The Link Whisper Free plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the user_id parameter in all versions up to, and including, 0.9.0 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticate…
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High 8.7CVE-2026-47761 Public exploit
TinyMCE Cross-Site Scripting (XSS) vulnerability using media plugin `data-mce-object` injection
TinyMCE is an open source rich text editor. Prior to 5.11.1, 7.9.3, and 8.5.1, there is a stored XSS vulnerability in the media plugin. Attackers can inject malicious scripts via crafted data-mce-* attributes, which are executed when content is rendered. Impa…
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High 8.1
Microsoft Exchange Server Spoofing Vulnerability
Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network.
KEV May 15, 2026 -
High 7.3CVE-2026-6735 Public exploit
XSS within PHP-FPM status endpoint
In PHP versions 8.2.* before 8.2.31, 8.3.* before 8.3.31, 8.4.* before 8.4.21, 8.5.* before 8.5.6, due to improper sanitation of user data, it allows an attacker to compose an URL, which will cause the target to execute arbitrary JavaScript code (XSS) on the …