Weakness (CWE)
CWE-87: Improper Neutralization of Alternate XSS Syntax
The product does not neutralize or incorrectly neutralizes user-controlled input for alternate script syntax.
How to prevent it (5 mitigations)
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Implementation
Resolve all input to absolute or canonical representations before processing.
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Implementation
Carefully check each input parameter against a rigorous positive specification (allowlist) defining the specific characters and format allowed. All input should be neutralized, not just parameters that the user is supposed to specify, but all data in the request, including tag attributes, hidden fields, cookies, headers, the URL itself, and so forth. A common mistake that leads to continuing XSS vulnerabilities is to validate only fields that are expected to be redisplayed by the site. We often encounter data from the request that is reflected by the application server or the application that the development team did not anticipate. Also, a field that is not currently reflected may be used by a future developer. Therefore, validating ALL parts of the HTTP request is recommended.
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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-87
62 results · Feed
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Medium 4.8
InvoicePlane: Stored Cross-Site Scripting (XSS) via Client Email in Invoice and Quote Mailer Forms
InvoicePlane is a self-hosted open source application for managing invoices, clients, and payments. In version 1.7.2-beta-1, InvoicePlane stores client_email values without enforcing email syntax and renders them unescaped inside double-quoted value attribute…
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Medium 5.3
Dell SCG 5.0 Appliance versions prior to 5.36.00.16 and Dell SCG 5.0 Application versions prior to 5.36.00.00, contains…
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High 8.5
Kirby: Cross-site scripting (XSS) from incomplete HTML/XML sanitization in `Dom::sanitize()`
Kirby is an open-source content management system. Prior to 4.9.4 and 5.4.4, Kirby sites and plugins that use the writer or list fields or call Dom::sanitize(), Sane::sanitize(), Sane::Html::sanitize(), Sane::Svg::sanitize(), Sane::Xml::sanitize(), Sane::sani…
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Medium 4.8
TinaCMS rich-text (slatejson) rendering does not sanitize link/image URLs, allowing stored XSS via dangerous URL schemes
Tina is a headless content management system. In versions prior to @tinacms/mdx 2.1.7 and tinacms 3.9.3, rich-text parsing and the default link/image renderers did not sanitize the url field on Slate link/image nodes. Content containing javascript: or data:te…
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High 8.8
AutoGPT SignUp Page has DOM-Based XSS and Open Redirect
AutoGPT is a workflow automation platform for creating, deploying, and managing continuous artificial intelligence agents. Versions prior to 0.6.62 have a DOM-based Cross-Site Scripting (XSS) vulnerability in AutoGPT's signup page. The application improperly …
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High 7.2
md-fileserver: Stored/Reflected XSS when viewing Markdown (raw HTML allowed)
md-fileserver allows for local viewing of markdown files in a browser. Prior to version 1.10.3, a cross-site scripting (XSS) vulnerability exists in the application’s Markdown rendering logic. When user-supplied Markdown content is rendered, embedded raw HTML…
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Medium 6.1
Apache Answer: XSS in AI Answer Rendering
Improper Neutralization of Alternate XSS Syntax vulnerability in Apache Answer. This issue affects Apache Answer: through 2.0.0. AI-generated response content was rendered in the browser without proper sanitization, allowing malicious scripts to be executed w…
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High 7.4
Open WebUI: XSS via SVG in /api/v1/channels/webhooks/{webhook_id}/profile/image
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.3, the channel webhook create/update flow accepts arbitrary profile_image_url values, including data:image/svg+xml;base64,... payloads. The profile…
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Medium 5.3
Magento LTS: Reflected XSS - Import -> Data Flow (profiles)
Magento Long Term Support (LTS) is an unofficial, community-driven project provides an alternative to the Magento Community Edition e-commerce platform with a high level of backward compatibility. Prior to 20.18.0, there is a reflected XSS vulnerability under…
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High 8.8
n8n: XSS via MCP OAuth client
n8n is an open source workflow automation platform. Prior to versions 1.123.32, 2.17.4, and 2.18.1, an unauthenticated attacker could register a malicious MCP OAuth client with a crafted client_name. If a victim user authorized the OAuth consent dialog and a …
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High 8.1
DotNetNuke.Core has stored cross-site-scripting (XSS) via SVG upload
DNN (formerly DotNetNuke) is an open-source web content management platform (CMS) in the Microsoft ecosystem. Prior to version 10.2.2, a user could upload a specially crafted SVG file that could include scripts that can target both authenticated and unauthent…
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Medium 6.4
Elementor Website Builder <= 3.35.5 - Authenticated (Contributor+) Stored Cross-Site Scripting via REST API
The Elementor Website Builder – More Than Just a Page Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via several widget parameters in all versions up to, and including, 3.35.5 due to insufficient input sanitization and output escapi…
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Medium 6.9
Stored XSS through system messages in WikiLove
Improper neutralization of alternate XSS syntax vulnerability in The Wikimedia Foundation Mediawiki - Wikilove Extension allows Cross-Site Scripting (XSS).The issue has been remediated on the `master` branch, and in the release branches for MediaWiki versions…
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High 7.6
ChurchCRM has Stored XSS in PersonView.php via Facebook Field Attribute Injection
ChurchCRM is an open-source church management system. Prior to 7.1.0, a stored cross-site scripting vulnerability exists in PersonView.php due to incorrect use of sanitizeText() as an output sanitizer for HTML attribute context. The function only strips HTML …
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High 8.8
DOM-Based XSS in Homarr /auth/login Redirect
Homarr is an open-source dashboard. Prior to 1.57.0, a DOM-based Cross-Site Scripting (XSS) vulnerability has been discovered in Homarr's /auth/login page. The application improperly trusts a URL parameter (callbackUrl), which is passed to redirect and router…
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High 7.1
YesWiki has Persistant Blind XSS at "/?BazaR&vue=consulter"
YesWiki is a wiki system written in PHP. Prior to version 4.6.0, a stored and blind XSS vulnerability exists in the form title field. A malicious attacker can inject JavaScript without any authentication via a form title that is saved in the backend database.…
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High 8.8
DOM-Based XSS in Ory Polis Login Page
Ory Polis, formerly known as BoxyHQ Jackson, bridges or proxies a SAML login flow to OAuth 2.0 or OpenID Connect. Versions prior to 26.2.0 contain a DOM-based Cross-Site Scripting (XSS) vulnerability in Ory Polis's login functionality. The application imprope…
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Medium 5.1
Chamilo: Reflected XSS via page parameter
Chamilo is a learning management system. Prior to version 1.11.30, there is a reflected cross-site scripting (XSS) vulnerability due to insufficient sanitization of the page parameter in the session/add_users_to_session.php endpoint. This issue has been patch…
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Medium 6.1
Leaf-kit html escaping does not work on characters that are part of extended grapheme cluster
Leafkit is a templating language with Swift-inspired syntax. Prior to 1.4.1, htmlEscaped in leaf-kit will only escape html special characters if the extended grapheme clusters match, which allows bypassing escaping by using an extended grapheme cluster contai…
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Critical 9.3
Node-SAML SAML Authentication Bypass
Node-SAML is a SAML library not dependent on any frameworks that runs in Node. In versions 5.0.1 and below, Node-SAML loads the assertion from the (unsigned) original response document. This is different than the parts that are verified when checking signatur…
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Low 3.3
Contao is vulnerable to cross-site scripting in templates
Contao is an Open Source CMS. From version 4.0.0 to before 4.13.57, before 5.3.42, and before 5.6.5, it is possible to inject code into the template output that will be executed in the browser in the front end and back end. This issue has been patched in vers…
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Medium 5.3
Galette is vulnerable to Cross-site Scripting
Galette is a membership management web application for non profit organizations. Versions 1.1.5.2 and below allow a user to edit a group name and insert an XSS payload. This issue is fixed in version 1.2.0.
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Medium 6.9
bagisto - Cross Site Scripting (XSS) in TinyMCE Image Upload (HTML)
Bagisto is an open source laravel eCommerce platform. In Bagisto v2.3.7, the TinyMCE image upload functionality allows an attacker with sufficient privileges (e.g. admin) to upload a crafted HTML file containing embedded JavaScript. When viewed, the malicious…
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Medium 6.9
bagisto - Cross Site Scripting (XSS) in TinyMCE Image Upload (SVG)
Bagisto is an open source laravel eCommerce platform. In Bagisto v2.3.7, the TinyMCE image upload functionality allows an attacker with sufficient privileges (e.g. admin) to upload a crafted SVG file containing embedded JavaScript. When viewed, the malicious …
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Medium 6.9
bagisto - Cross Site Scripting (XSS) in Create New Customer
Bagisto is an open source laravel eCommerce platform. In Bagisto v2.3.7, the “Create New Customer” feature (in the admin panel) is vulnerable to Cross-Site Scripting (XSS). An attacker with access to the admin create-customer form can inject malicious JavaScr…
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Medium 6.4
Ova Advent <= 1.1.7 - Authenticated (Contributor+) Stored Cross-Site Scripting via Shortcode
The Ova Advent plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's shortcodes in all versions up to, and including, 1.1.7 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it poss…
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High 7.1
Shaarli allows reflected XSS via searchtags parameter
Shaarli is a minimalist bookmark manager and link sharing service. Prior to 0.15.0, the input string in the cloud tag page is not properly sanitized. This allows the </title> tag to be prematurely closed, leading to a reflected Cross-Site Scripting (XSS) vuln…
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Medium 5.2
Group-Office vulnerable to blind XSS
Group-Office is an enterprise customer relationship management and groupware tool. Prior to versions 6.8.123 and 25.0.27, a stored and blind cross-site scripting (XSS) vulnerability exists in the Name Field of the user profile. A malicious attacker can change…
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High 8.5
Hax CMS Stored Cross-Site Scripting vulnerability
HAX CMS PHP allows users to manage their microsite universe with a PHP backend. Prior to version 11.0.0, the application does not sufficiently sanitize user input, allowing for the execution of arbitrary JavaScript code. The 'saveNode' and 'saveManifest' endp…
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Medium 4.8
Gokapi has stored XSS vulnerability in friendly name for API keys
Gokapi is a self-hosted file sharing server with automatic expiration and encryption support. By renaming the friendly name of an API key, an authenticated user could inject JS into the API key overview, which would also be executed when another user clicks o…
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Medium 4.8
Gokapi vulnerable to stored XSS via uploading file with malicious file name
Gokapi is a self-hosted file sharing server with automatic expiration and encryption support. When using end-to-end encryption, a stored cross-site scripting vulnerability can be exploited by uploading a file with JavaScript code embedded in the filename. Aft…
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Medium 6.9
GroupOffice's Blind Stored XSS in Phone Number Field Enables Forced Redirect and Unauthorized Actions
Group-Office is an enterprise customer relationship management and groupware tool. Prior to versions 6.8.119 and 25.0.20, a stored and blind XSS vulnerability exists in the Phone Number field of the user profile within the GroupOffice application. This allows…
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Medium 5.3
Open WebUI vulnerable to limited stored XSS vila uploaded html file
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to version 0.6.6, low privileged users can upload HTML files which contain JavaScript code via the `/api/v1/files/` backend endpoint. This endpoint return…
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Medium 5.3
Vega vulnerable to Cross-site Scripting via RegExp.prototype[@@replace]
Vega is a visualization grammar, a declarative format for creating, saving, and sharing interactive visualization designs. In Vega prior to version 5.32.0, corresponding to vega-functions prior to version 5.17.0, users running Vega/Vega-lite JSON definitions …
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Medium 6.4
WordPress Infinite Scroll - Ajax Load More <= 7.1.2 - Authenticated (Contributor+) Stored Cross-Site Scripting via button_label Parameter
The WordPress Infinite Scroll – Ajax Load More plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘button_label’ parameter in all versions up to, and including, 7.1.2 due to insufficient input sanitization and output escaping. This make…
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Medium 5.0
reNgine vulnerable to Stored Cross-Site Scripting (XSS) via DNS Record Poisoning
reNgine is an automated reconnaissance framework for web applications. Versions 2.1.2 and prior are susceptible to Stored Cross-Site Scripting (XSS) attacks. This vulnerability occurs when scanning a domain, and if the target domain's DNS record contains an X…
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Medium 6.4
Themesflat Addons For Elementor <= 2.1.2 - Authenticated (Contributor+) Stored Cross-Site Scripting via Widget Titles
The Themesflat Addons For Elementor plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's widget's titles in all versions up to, and including, 2.1.2 due to insufficient input sanitization and output escaping on user supplied attr…
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Medium 4.4
Font Farsi <= 1.6.6 - Authenticated (Administrator+) Stored Cross-Site Scripting
The Font Farsi plugin for WordPress is vulnerable to Stored Cross-Site Scripting via admin settings in all versions up to, and including, 1.6.6 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, wit…
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Medium 6.4
Elementor Header & Footer Builder <= 1.6.26 - Authenticated (Contributor+) Stored Cross-Site Scripting
The Elementor Header & Footer Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the size attribute in all versions up to, and including, 1.6.26 due to insufficient input sanitization and output escaping. This makes it possible for …
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Medium 6.4
Opal Estate Pro – Property Management and Submission <= 1.7.6 - Authenticated (Contributor+) Stored Cross-Site Scripting
The Opal Estate Pro – Property Management and Submission plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the agent latitude and longitude parameters in all versions up to, and including, 1.7.6 due to insufficient input sanitization and o…