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
591 results · Clear filters · Feed
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Critical 9.0
SiYuan before v3.7.4 Stored XSS via Attribute-View Field Names
SiYuan before v3.7.4 stores attribute-view field names without HTML escaping and interpolates them directly into option elements via innerHTML in the sort menu. Attackers can inject markup by renaming a database field to execute arbitrary JavaScript when user…
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Critical 9.0
SiYuan before v3.7.4 Stored XSS via select option color
SiYuan versions before v3.7.4 fail to validate or escape the color field in attribute-view select options, allowing stored cross-site scripting through eight unescaped render sites. Attackers can inject event-handler attributes by including quotation marks in…
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Critical 9.0
SiYuan before v3.7.4 Stored Cross-Site Scripting via Column Width
SiYuan versions before v3.7.4 fail to validate or escape table column width values, allowing stored cross-site scripting injection into style attributes. Attackers can inject malicious payloads through the setAttrViewColWidth API that break out of style attri…
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Critical 9.0
SiYuan before v3.7.4 Remote Code Execution via Template Calculation
SiYuan versions before v3.7.4 contain a remote code execution vulnerability in the Template calculation operator, which renders user-authored Go templates and stores output verbatim without sanitization. Attackers can inject malicious HTML and JavaScript into…
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Critical 9.0
SiYuan before v3.7.4 Remote Code Execution via PDF Annotations
SiYuan versions before v3.7.4 fail to validate or escape annotation fields written to disk by the setFileAnnotation endpoint. Attackers can inject malicious markup into annotation fields that execute as script in the PDF renderer with full Node.js access when…
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Critical 9.0
SiYuan before v3.7.4 Remote Code Execution via Menu Metadata
SiYuan before v3.7.4 fails to properly escape database menu metadata in HTML interpolation, allowing stored values to execute script when users open group, view, or field-edit menus. Attackers can inject markup through field descriptions or names that close c…
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Critical 9.3
Microsoft Office SharePoint Spoofing Vulnerability
Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Office SharePoint allows an unauthorized attacker to perform spoofing over a network.
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Critical 9.6
Microsoft Office SharePoint Spoofing Vulnerability
Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Office SharePoint allows an unauthorized attacker to perform spoofing over a network.
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Critical 9.3
Cross-site scripting in Progress MarkLogic Server Query Console
A cross-site scripting vulnerability in the Query Console of Progress MarkLogic Server before 11.3.6 and 12.0.3 allows a remote attacker who lures an authenticated administrator to a crafted URL to execute arbitrary JavaScript in the administrator's browser s…
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Critical 9.3CVE-2026-66421 Public exploit
OpenClaw Dashboard Stored XSS via lastMessage Session Field
OpenClaw Dashboard contains a stored cross-site scripting vulnerability that allows unauthenticated remote attackers to execute arbitrary JavaScript in the administrator's browser session by injecting HTML markup into agent transcript messages processed throu…
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Critical 9.3CVE-2026-66418 Public exploit
OpenClaw Dashboard v3.0.0 Stored XSS via Failed Login Username Field
OpenClaw Dashboard v3.0.0 contains a stored cross-site scripting vulnerability that allows unauthenticated remote attackers to inject arbitrary HTML and script payloads by submitting a crafted username in a failed login POST request, which is recorded verbati…
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Critical 9.3
Multiple vulnerabilities have been identified in IBM WebSphere Application Server shipped with Tivoli System Automation Application Manager
IBM Tivoli System Automation Application Manager 4.1 and IBM WebSphere Application Server is affected by a cross-site scripting vulnerability in the administrative console login page.
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Critical 9.2
DOM-Based Cross-Site Scripting via Unsafe String and SVG Icon Rendering in Pivotick
Pivotick contains a DOM-based cross-site scripting vulnerability in its generic UI element resolution and icon-rendering utilities. The tryResolveHTMLElement function treated any resolved string as HTML markup by assigning it to a <template> element through i…
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Critical 9.2
Stored Cross-Site Scripting via Unsafe Capture Tree JSON Embedding
A stored cross-site scripting vulnerability existed in the capture tree visualization page. The application embedded the serialized capture tree directly into an inline JavaScript block using the Jinja safe filter. Because the tree data can contain values der…
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Critical 9.6
SiYuan Desktop before v3.7.2 Reflected XSS to RCE via siyuan Protocol
SiYuan desktop before v3.7.2 contains a reflected cross-site scripting vulnerability in the bazaar plugin readme handler that allows attackers to execute arbitrary code by crafting a malicious siyuan:// deep link. Attackers can inject HTML payloads via the pl…
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Critical 9.6
SiYuan before v3.7.2 Cross-Site Scripting to RCE
SiYuan before v3.7.2 contains a cross-site scripting vulnerability in the siyuan:// protocol handler. When a siyuan://plugins/<name> link references a name that is not an installed plugin, the application opens a custom tab and inserts the link's icon paramet…
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Critical 9.6
SiYuan before v3.7.2 Stored XSS to RCE via Attribute View
SiYuan before v3.7.2 contains a stored cross-site scripting vulnerability in Attribute View (database) cell rendering. A Template column value is rendered as HTML via text/template without auto-escaping, and EscapeHTML is only applied when HasUnclosedHtmlTag …
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Critical 9.3
Ninja Forms Unauthenticated Stored Cross-Site Scripting via Repeatable Fieldset Submission Index
Ninja Forms plugin for WordPress versions 3.10.4 through 3.14.9 contains an unauthenticated stored cross-site scripting vulnerability in the Repeatable Fieldset feature where parseSubmissionIndex() accepts arbitrary strings as submission indexes without numer…
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Critical 9.4
Joomla Extension - themexpert.com - Authenticated stored XSS in JMedia Extension < 1.6.0
Joomla Extension - themexpert.com - Authenticated stored XSS in JMedia Extension < 1.6.0 - The Joomla extension JMedia is vulnerable to a stored XSS vulnerability. Unsanitised SVG uploads served without nosniff, leading to stored/reflected XSS.
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Critical 9.3
Chamilo stored XSS via user registration leads to admin account takeover
Chamilo LMS versions 1.11.38 and earlier contain a stored cross-site scripting vulnerability in the user registration form that allows any unauthenticated attacker to execute arbitrary JavaScript in an administrator's browser session, leading to full platform…
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Critical 9.0
HeyForm vulnerable to stored XSS via form field titles
HeyForm is an open-source form builder. Prior to version 3.0.0-rc.7, a stored cross-site scripting (XSS) vulnerability in the form builder allows a low-privileged team member to inject malicious JavaScript that executes when a team owner views the form, leadi…
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Critical 9.3
Multiple Vulnerabilities in IBM Engineering AI hub.
IBM Engineering AI Hub 1.0.0, 1.1.0, and 1.2.0 could allow a remote attacker to execute arbitrary scripts due to improper neutralization of input during web page generation.
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Critical 9.6
AVideo: Unauthenticated Stored DOM Cross-Site Scripting via Per-Client Metadata Broadcast in YPTSocket Plugin
WWBN AVideo is an open source video platform. Versions prior to 29.0 contain a stored DOM Cross-Site Scripting vulnerability in the YPTSocket plugin. Any unauthenticated remote attacker can execute arbitrary JavaScript in the authenticated origin of every adm…
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Critical —
MantisBT: Reflected XSS in admin/install.php via unescaped printf
MantisBT 2.28.3 and earlier contains six reflected XSS injection points in `/admin/install.php`. User-supplied parameters are echoed into HTML without escaping via an unescaped printf format string. No authentication is required. A Content Security Policy (sc…
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Critical —
MantisBT: Reflected XSS in admin/install.php
MantisBT 2.28.3 and earlier contains six reflected XSS injection points in `/admin/install.php`. User-supplied parameters are echoed into HTML without escaping via print_test_result(). No authentication is required. A Content Security Policy (script-src 'self…
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Critical 9.6
OpenWrt odhcpd/LuCI: unauthenticated DHCPv6 client can inject lease-file lines via FQDN hostname → stored XSS in the LuCI admin UI
OpenWrt is a Linux operating system targeting embedded devices. Prior to 25.12.5, odhcpd writes a DHCPv6 client FQDN option 39 hostname into /tmp/odhcpd.leases through src/statefiles.c statefiles_write_state6() and statefiles_write_state4() without escaping, …
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Critical 9.0
RustFS Console: Critical Stored XSS in Preview Modal leading to Administrative Account Takeover
RustFS Console is a web management console for the RustFS distributed file system. From 0.1.7 until 0.1.10, the RustFS Console components/object/preview-modal.tsx and components/object/pdf-viewer.tsx extension-based PDF preview path can render HTML content up…
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Critical 9.6
Vitest browser mode serves unsanitized otelCarrier query parameter as inline script
Vitest is a testing framework powered by Vite. From 4.0.17 until 4.1.6 and 5.0.0-beta.3, Vitest Browser Mode served /__vitest_test__/ with the otelCarrier query parameter inserted directly into an inline module script, allowing a crafted browser-runner URL to…
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Critical 9.6
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.
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Critical 9.8
Mother May I - Critical - Unsupported - SA-CONTRIB-2026-045
vulnerability in Drupal Mother May I allows . This issue affects Mother May I versions: *.*.
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Critical 9.3
OpenReplay: Unauthenticated stored XSS leads to dashboard account takeover
OpenReplay is a self-hosted session replay suite. From 1.24.0 before 1.25.0, the OpenReplay tracking SDK accepts custom event names and captured page URLs from any visitor using a public project key, stores them in ClickHouse without output encoding, and late…
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Critical 9.3
XSS in Oceanicsoft's ValeApp
Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in OceanicSoft Informatics Systems Ltd. ValeApp allows Stored XSS. This issue affects ValeApp: through 09072026. NOTE: The vendor was contacted early about this…
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Critical 9.3
Dynamics 365 Customer Voice Spoofing Vulnerability
Improper neutralization of input during web page generation ('cross-site scripting') in Dynamics 365 Customer Voice allows an unauthorized attacker to perform spoofing over a network.
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Critical 9.3
JupyterLab Git: Stored XSS leading to RCE
JupyterLab Git is a Git extension for JupyterLab. From 0.30.0b3 before 0.54.0, the PlainTextDiff.ts createHeader() method passes Git filenames directly to innerHTML when rendering renamed files in commit history, allowing a crafted filename to execute JavaScr…
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Critical 9.6
WordPress Admin and Site Enhancements (ASE) Pro plugin <= 8.8.5 - Cross Site Scripting (XSS) vulnerability
Unauthenticated Cross Site Scripting (XSS) in Admin and Site Enhancements (ASE) Pro <= 8.8.5 versions.
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Critical 9.3
IBM WebSphere Application Server is affected by a cross-site scripting vulnerability
IBM WebSphere Application Server 9.0, and 8.5 is affected by a cross-site scripting vulnerability in the administrative console's integrated help system.
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Critical 9.3
IBM WebSphere Application Server is affected by a cross-site scripting vulnerability
IBM WebSphere Application Server 9.0, and 8.5 is affected by a cross-site scripting vulnerability in the administrative console help system.
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Critical 9.0
SiYuan: Stored XSS results to Electron RCE in SiYuan marketplace via unescaped `data-obj` attribute (Bypass for CVE-2026-45375's patch)
SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, it does not escape the untrusted fields (name, version, author, description) when they are serialized into the data-obj HTML attribute of each marketplace card. Because the attribu…
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Critical 9.9
SiYuan: Stored XSS to RCE via Unsanitized Attribute View Asset Cell Content
SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, SiYuan contains a stored cross-site scripting (XSS) vulnerability in the Attribute View (database) asset cell renderer that escalates to remote code execution (RCE) in the Electron…
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Critical 9.9
SiYuan: Stored XSS to RCE via attribute-view cell rendering in genAVValueHTML()
SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, the attribute-view (database) cell renderer genAVValueHTML interpolates cell content raw in four of its branches: text, url, phone, and mAsset. A cell value like </textarea><img sr…