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
21,917 results · Clear filters · Feed
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Medium 6.1
Advanced Ads – Ad Manager & AdSense < 2.0.23 - Contributor+ Stored XSS via the_ad Shortcode 'ad_args' Parameter
The Advanced Ads WordPress plugin before 2.0.23 does not sanitize and escape a shortcode parameter before outputting it in the page, allowing users with the Contributor role and above to inject arbitrary web scripts that execute when the affected content is v…
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Medium 6.1CVE-2026-51565 Public exploit
Cross-site scripting (XSS) vulnerability in Modules/Docs/DocsController.php in Milk admin <=0.9.8 allows remote attacke…
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Medium 6.4
Yoast SEO <= 28.0 - Authenticated (Author+) Stored Cross-Site Scripting via Post Slug (post_name)
The Yoast SEO – Advanced SEO with real-time guidance and built-in AI plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Post Slug (post_name) in all versions up to, and including, 28.0 due to insufficient input sanitization and output escap…
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Medium 5.4
Milkdown < 7.21.3 DOM XSS via innerHTML Assignment
Milkdown before 7.21.3 contains a DOM cross-site scripting vulnerability in the @milkdown/plugin-emoji package that allows unauthenticated attackers to execute arbitrary JavaScript in the host application's origin by causing a victim to paste attacker-control…
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Medium 5.4
Milkdown < 7.21.3 Stored XSS via javascript: URL in link href
Milkdown before 7.21.3 contains a stored cross-site scripting vulnerability in the @milkdown/preset-commonmark and @milkdown/components packages that allows attackers with document write access to execute arbitrary JavaScript in the browser context of any use…
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Medium 5.7
ImageMagick: Code injection in HTML encoder due to incomplete fix of CVE-2026-25797
An incomplete fix of CVE-2026-25797 can result in code injection in the HTML encoder.
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Medium 6.1
Reflected XSS Polen Media's Website Template
Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in Polen Media Software and Information Services Website Template allows Reflected XSS. This issue affects Website Template: before v2.
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Medium 6.1
DOMPurify before 3.4.12 Hook Bypass via CUSTOM_ELEMENT_HANDLING
DOMPurify before 3.4.12 fails to execute afterSanitizeElements hook for custom elements allowed via CUSTOM_ELEMENT_HANDLING.tagNameCheck, allowing attributes to bypass application security policies. Attackers can preserve sensitive attributes on custom elemen…
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Medium 6.1
VikBooking Hotel Booking Engine & PMS <= 1.8.13 - Reflected Cross-Site Scripting via 'category_id' Parameter
The VikBooking Hotel Booking Engine & PMS plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'category_id' parameter in all versions up to, and including, 1.8.13 due to insufficient input sanitization and output escaping. This makes …
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Medium 6.4
Rich Showcase for Google Reviews <= 6.9.9 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'pagination' Shortcode Attribute
The Rich Showcase for Google Reviews plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'pagination' Shortcode Attribute in all versions up to, and including, 6.9.9 due to insufficient input sanitization and output escaping. This makes it p…
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Medium 6.4
SureDash <= 1.10.0 - Authenticated (Contributor+) Stored Cross-Site Scripting via Shortcode Attributes
The SureDash – Community, Courses & Member Dashboard plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Shortcode Attributes in all versions up to, and including, 1.10.0 due to insufficient input sanitization and output escaping. This makes…
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Medium 6.4
WP Hotel Booking <= 2.3.2 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'widget_search' Shortcode Attribute
The WP Hotel Booking plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'widget_search' Shortcode Attribute in all versions up to, and including, 2.3.2 due to insufficient input sanitization and output escaping. This makes it possible for a…
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Medium 6.4
Visualizer <= 4.0.5 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'backend-title' Parameter
The Visualizer – Tables & Charts Manager with Built-in AI Generator plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'backend-title' parameter in all versions up to, and including, 4.0.5 due to insufficient input sanitization and outp…
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Medium 6.4
Brands for WooCommerce <= 3.8.8 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'width' Shortcode Attribute
The Brands for WooCommerce plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'width' Shortcode Attribute in all versions up to, and including, 3.8.8 due to insufficient input sanitization and output escaping. This makes it possible for aut…
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Medium 6.4
Open User Map <= 1.4.45 - Authenticated (Contributor+) Stored Cross-Site Scripting via Shortcode Attributes
The Open User Map – Interactive Leaflet Maps plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Shortcode Attributes in all versions up to, and including, 1.4.45 due to insufficient input sanitization and output escaping. This makes it poss…
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Medium 6.4
Cozy Blocks <= 2.2.11 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'icon.view' Block Attribute
The Cozy Blocks – Page Builder for Gutenberg Editor & FSE with 600+ Patterns, 58 Blocks & Templates plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'icon.view' Block Attribute in all versions up to, and including, 2.2.11 due to insuffici…
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Medium 6.4
Cozy Blocks <= 2.2.11 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'cozyCustomFont' Block Attribute
The Cozy Blocks – Page Builder for Gutenberg Editor & FSE with 600+ Patterns, 58 Blocks & Templates plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'cozyCustomFont' Block Attribute in all versions up to, and including, 2.2.11 due to insu…
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Medium 6.4
Fluent Support <= 2.3.0 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'redirect-to' Shortcode Attribute
The Fluent Support – Helpdesk & Customer Support Ticket System plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'redirect-to' Shortcode Attribute in all versions up to, and including, 2.3.0 due to insufficient input sanitization and outpu…
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Medium 6.4
MapSVG Lite <= 8.14.0 - Authenticated (Contributor+) Stored Cross-Site Scripting
The MapSVG plugin for WordPress is vulnerable to Stored Cross-Site Scripting in all versions up to, and including, 8.14.0. This is due to insufficient input sanitization and output escaping on user supplied attributes within the map options. This makes it pos…
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Medium 6.4
Firelight Lightbox <= 2.3.20 - Authenticated (Contributor+) Stored DOM Cross-Site Scripting via PDF beforeLoad 'href' Attribute
The Firelight Lightbox plugin for WordPress is vulnerable to Stored DOM Cross-Site Scripting in versions up to and including 2.3.20. This is due to insufficient sanitization of the href attribute value within the FancyBox V2 PDF beforeLoad JavaScript callback…
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Medium 6.4
Post Grid Gutenberg Blocks <= 5.0.32 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'searchnoresult' Block Attribute
The Post Grid Gutenberg Blocks – PostX plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'searchnoresult' Block Attribute in all versions up to, and including, 5.0.32 due to insufficient input sanitization and output escaping. This makes i…
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Medium 5.1
Joomla Extension - phoca.cz - Reflected XSS vulnerability in Phoca Guestbook 5.0.0-6.1.0
Joomla Extension - phoca.cz - Reflected XSS vulnerability in Phoca Guestbook 5.0.0-6.1.0 - Improper validation of user inputs lead to a reflective XSS vulnerability.
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Medium 5.1
Joomla Extension - phoca.cz - Reflected XSS vulnerability in Phoca Maps 5.0.0-6.0.4
Joomla Extension - phoca.cz - Reflected XSS vulnerability in Phoca Maps 5.0.0-6.0.4 - Improper validation of user inputs lead to a reflective XSS vulnerability.
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Medium 6.1
Fathom Lite 1.3.1 Stored XSS via /collect Endpoint
Fathom Lite through 1.3.1 contains a stored cross-site scripting vulnerability in the analytics collection endpoint that allows unauthenticated attackers to inject a javascript: URI into the Top Pages dashboard by supplying a crafted hostname and pathname to …
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Medium 5.4
GFI Archiver < 15.14 Stored XSS via MailInsights.aspx
GFI Archiver before 15.14 contains a stored cross-site scripting vulnerability in the MailInsights scheduled report configuration that allows authenticated attackers to inject arbitrary web script or HTML via the report name parameter to /Archiver/MailInsight…
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Medium 5.4
GFI Archiver < 15.13 Stored XSS via ImportSettingsWizard.ashx
GFI Archiver before 15.13 contains a stored cross-site scripting vulnerability in the default import settings configuration that allows authenticated attackers to inject arbitrary web script or HTML via the configured folders parameter to /Archiver/ImportSett…
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Medium 5.4
GFI Archiver < 15.13 Stored XSS via FileArchiveAssistantWizard.aspx
GFI Archiver before 15.13 contains a stored cross-site scripting vulnerability in the File Archive Assistant configuration that allows authenticated attackers to inject arbitrary web script or HTML via the excluded extensions parameter to /Archiver/FileArchiv…
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Medium 5.4
GFI Archiver < 15.13 Stored XSS via GeneralSettingsWizard.aspx
GFI Archiver before 15.13 contains a stored cross-site scripting vulnerability in the General Settings SMTP configuration that allows authenticated attackers to inject arbitrary web script or HTML via the SMTP server address parameter to /Archiver/GeneralSett…
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Medium 5.4
GFI Archiver < 15.13 Stored XSS via CallHomeSettingsWizard.aspx
GFI Archiver before 15.13 contains a stored cross-site scripting vulnerability in the Call Home proxy server configuration that allows authenticated attackers to inject arbitrary web script or HTML via the proxy server address parameter to /Archiver/CallHomeS…
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Medium 5.4
GFI Archiver < 15.13 Stored XSS via ImapServerWizard.aspx
GFI Archiver before 15.13 contains a stored cross-site scripting vulnerability in the IMAP Server configuration that allows authenticated attackers to inject arbitrary web script or HTML via the server URL parameter to /Archiver/ImapServerWizard.aspx. The inj…
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Medium 5.4
GFI Archiver < 15.13 Stored XSS via FAARetentionPolicyWizard.aspx
GFI Archiver before 15.13 contains a stored cross-site scripting vulnerability in the File History Retention Policy configuration that allows authenticated attackers to inject arbitrary web script or HTML via the policy name parameter to /Archiver/FAARetentio…
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Medium 5.4
GFI Archiver < 15.13 Stored XSS via RetentionPolicyWizard.aspx
GFI Archiver before 15.13 contains a stored cross-site scripting vulnerability in the Retention Policy configuration that allows authenticated attackers to inject arbitrary web script or HTML via the policy name parameter to /Archiver/RetentionPolicyWizard.as…
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Medium 5.4
GFI Archiver < 15.14 Stored XSS via CategorizationPolicyWizard.aspx
GFI Archiver before 15.14 contains a stored cross-site scripting vulnerability in the Classification Rules configuration that allows authenticated attackers to inject arbitrary web script or HTML via the rule name and email criteria parameters to /Archiver/Ca…
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Medium 5.3
DOMPurify before 3.3.2 Mutation XSS via Re-Contextualization
DOMPurify before 3.3.2 contains a mutation-XSS vulnerability when sanitized HTML is reinserted into special parsing contexts using innerHTML with wrappers like script, xmp, iframe, noembed, noframes, or noscript. Attackers can craft payloads with closing sequ…
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Medium 6.1
DOMPurify before 3.3.2 URI Validation Bypass via ADD_ATTR
DOMPurify before 3.3.2 contains a URI validation bypass vulnerability when ADD_ATTR is provided as a predicate function via EXTRA_ELEMENT_HANDLING.attributeCheck. Attackers can supply a predicate that accepts specific attribute and tag combinations to bypass …
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Medium 6.1
DOMPurify before 3.4.0 XSS via ADD_ATTR/ADD_TAGS State Leakage
In DOMPurify through 3.3.3, function predicates supplied via ADD_ATTR or ADD_TAGS to DOMPurify.sanitize() persist in internal state (EXTRA_ELEMENT_HANDLING) across subsequent sanitize() calls on the same instance. If a later call on the same instance provides…
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Medium 6.1
DOMPurify before 3.4.8 Template Expression Injection via RETURN_DOM
DOMPurify versions >=3.0.0 and before 3.4.8, when configured with SAFE_FOR_TEMPLATES together with a DOM output mode (RETURN_DOM, RETURN_DOM_FRAGMENT, or IN_PLACE), fail to strip template expressions (e.g. ${evil}, {{evil}}, <%evil%>) inside <template> elemen…
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Medium 6.1
DOMPurify 3.4.6 Cross-Site Scripting via IN_PLACE nodeName
DOMPurify through 3.4.6 contains a cross-site scripting vulnerability in IN_PLACE mode that trusts attacker-controlled nodeName on live non-form nodes. Attackers can supply hostile live DOM objects with real script children whose observable nodeName is clobbe…
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Medium 6.5
WordPress Modula Image Gallery plugin 2.14.25-2.14.30 - Cross Site Scripting (XSS) vulnerability
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in WP Chill Modula Image Gallery allows Stored XSS. This issue affects Modula Image Gallery: from 2.14.25 through 2.14.30.
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Medium 4.3
In JetBrains IntelliJ IDEA before 2026.2 hTML injection was possible in an IDE notification, allowing silent user activ…