Weakness (CWE)
CWE-83: Improper Neutralization of Script in Attributes in a Web Page
The product does not neutralize or incorrectly neutralizes "javascript:" or other URIs from dangerous attributes within tags, such as onmouseover, onload, onerror, or style.
How to prevent it (4 mitigations)
-
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.
-
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.
-
Implementation
With Struts, write all data from form beans with the bean's filter attribute set to true.
-
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-83
12 results · Clear filters · Feed
-
High 8.2
GFI KerioConnect < 10.0.8p2 Stored XSS via SVG Attachment
GFI KerioConnect (Kerio Connect) before 10.0.8 Patch 2 contains a stored cross-site scripting vulnerability in the Webmail component that allows a remote attacker to run JavaScript in a victim's authenticated Webmail session by uploading a crafted SVG email a…
-
High 7.4
OCO-Server: Stored XSS through agent hostnames in command buttons
OCO-Server is a self-hosted endpoint management application for computer inventory, software deployment, and mobile device management. Prior to 1.2.1, `Html::commandButton()` in `lib/Html.class.php` embeds an action URL containing a stored computer hostname i…
-
High 7.6
@tinacms/web-components: `tina-markdown` writes rich-text link URLs into `href` without scheme validation, allowing stored XSS
Tina is a headless content management system. Prior to 0.2.1, the tina-markdown element in packages/@tinacms/web-components/src/tina-markdown.js assigns a rich-text node.url value directly to an anchor href without validating the URL scheme. A content author …
-
High 8.2
File Viewer: DOM XSS via unsafe hyperlink schemes in the legacy DOC renderer
File Viewer is a browser-native viewer for Office, PDF, CAD, archive, and other files in private and internal web applications. Prior to @file-viewer/doc 2.3.1 and msdoc-viewer 0.2.2, the legacy DOC renderer emitted document-controlled hyperlink targets into …
-
High 8.3
Trilium: Stored XSS in note icon rendering leads to Remote Code Execution in Electron desktop app
Trilium Notes is a cross-platform, hierarchical note taking application focused on building large personal knowledge bases. Prior to 0.103.0, the #iconClass label value is returned raw by getNoteIcon() and inserted without HTML attribute encoding into class a…
-
High 7.4
Kirby: Self cross-site scripting (self-XSS) in the writer field
Kirby is an open-source content management system. Prior to 4.9.4 and 5.4.4, Kirby sites using the writer field in any blueprint allowed a scripting link to be included as the target of a link or email link in writer mark components, making the target clickab…
-
High 7.2
Jodit Editor: Mutation XSS in jodit clean-html via a MathML/style rawtext carrier
Jodit Editor is a WYSIWYG editor with a built-in file browser & image editor. In versions prior to 4.12.28, the built-in clean-html sanitizer can be bypassed by a MathML/<style> carrier that hides a dangerous element from the sanitizer's element walk, so a no…
-
High 8.6
CVAT vulnerable to XSS via skeleton SVG images
CVAT is an open source interactive video and image annotation tool for computer vision. In versions 2.2.0 through 2.54.0, an attacker is able to execute arbitrary JavaScript in a victim user's CVAT UI session, provided that they are able to create a malicious…
-
High 7.2CVE-2026-22849 Public exploit
Saleor lacks proper HTML sanitization in rich text fields
Saleor is an e-commerce platform. Starting in version 3.0.0 and prior to versions 3.20.108, 3.21.43, and 3.22.27, Saleor was allowing users to modify rich text fields with HTML without running any backend HTML cleaners thus allowing malicious actors to perfor…
-
High 7.1
Stored Cross-Site Scripting in Perx Customer Engagement & Loyalty Platform
Stored cross-site scripting (XSS) vulnerability in the LMT Dashboard of the Perx Customer Engagement & Loyalty Platform allows an authenticated attacker to execute arbitrary JavaScript code in a victim's browser. The vulnerability is due to improper sanitizat…
-
High 7.7
HTML Cleaner allows crafted scripts in special contexts like svg or math to pass through
lxml_html_clean is a project for HTML cleaning functionalities copied from `lxml.html.clean`. Prior to version 0.4.0, the HTML Parser in lxml does not properly handle context-switching for special HTML tags such as `<svg>`, `<math>` and `<noscript>`. This beh…
-
High 7.8
An attacker could have executed unauthorized scripts on top origin sites using a JavaScript URI when opening an externa…