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OpenAdvisories

Weakness (CWE)

CWE-79: Cross-site Scripting

Base Improper Neutralization of Input During Web Page Generation

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)
  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Implementation

    With Struts, write all data from form beans with the bean's filter attribute set to true.

  8. 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

32,779 results · Feed

  • Low 3.5

    Helium: Stored XSS via Unrestricted SVG File Upload — Authenticated Users Can Store Executable Scripts

    Helium is a free online student planner for classes, homework, grades, and notes. Prior to 2.2.60, the POST /planner/attachments/ endpoint allows authenticated users to upload SVG and HTML attachments because conf/configs/common.py omits those formats from BL…

  • High 7.1

    WordPress XStore theme < 9.7.9 - Cross Site Scripting (XSS) vulnerability

    Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in 8theme.com XStore xstore allows Reflected XSS.This issue affects XStore: from n/a before 9.7.9.

  • Medium 5.7

    Lychee: Stored XSS via Markdown javascript: Links in Photo and Album Descriptions (Gallery View)

    Lychee is a free, open-source photo-management tool. Prior to 7.6.0, Lychee permits an authenticated user with album-edit permissions to store a javascript URI in an album or photo Markdown description because config/markdown.php enables allow_unsafe_links. a…

  • Medium 5.1

    Nexus Repository 3 - Stored Cross-Site Scripting in Browse UI

    Sonatype Nexus Repository 3 allows a user account that holds the edit permission on a hosted R repository to store script content in the metadata of an uploaded R package. The script runs in the browser of a user who opens the details of that package in the B…

  • Medium 6.7

    In JetBrains TeamCity before 2026.2, 2026.1.4, 2025.11.8 stored XSS in the classic build log was possible

  • High 8.0

    In JetBrains TeamCity before 2026.2, 2026.1.4, 2025.11.8 stored XSS in the classic project overview was possible

  • High 8.0

    OPNsense: Stored XSS to root RCE via OpenVPN client common_name in status views

    OPNsense is a FreeBSD based firewall and routing platform. Prior to version 26.1.11, the OpenVPN connection-status dashboard widget in src/opnsense/www/js/widgets/OpenVPNClients.js and the connection-status view place a client common_name into data-common-nam…

  • Medium 5.2

    OPNsense: Stored XSS in Administration Settings via Certificate Description

    OPNsense is a FreeBSD based firewall and routing platform. Prior to version 26.1.11, src/www/system_advanced_admin.php reads certificate records into $a_cert but omits that array from legacy_html_escape_form_data() before rendering each certificate descr valu…

  • Medium 5.4

    OPNsense: Stored XSS in Services: NTP GPS

    OPNsense is a FreeBSD based firewall and routing platform. Prior to version 26.1.11, the NTP GPS page stores the operator-supplied initcmd value in base64 form, applies legacy_html_escape_form_data() to the encoded string, and then uses base64_decode() to dec…

  • Medium 5.4

    OPNsense: Stored XSS in Firewall Rules/NAT pages via a HTML-attribute breakout

    OPNsense is a FreeBSD based firewall and routing platform. Prior to version 26.1.11, Firewall Rules and NAT views place stored category names and alias descriptions into HTML title attributes in filter_rule.volt and nat_rule.volt without quote-safe encoding. …

  • Medium 4.3

    EspoCRM: Pre-authentication stored HTML injection in stream notification emails about email received

    EspoCRM is an open source customer relationship management application. Prior to 9.3.9, an unauthenticated remote attacker can send an email to a monitored group or IMAP address, including an email-to-Case address, and place arbitrary HTML in its plain-text b…

  • Low 3.5

    EspoCRM: Stored XSS in wysiwyg template fields if CSP is disabled

    EspoCRM is an open source customer relationship management application. Prior to 9.3.9, a user with Email Template or PDF Template edit permission can store crafted HTML that bypasses moderateSanitizeHtml(). When another user opens the template in edit mode a…

  • Low 2.7

    EspoCRM: Persistent XSS via CSP nonce injection in applicationName setting by admin user

    EspoCRM is an open source customer relationship management application. Prior to 9.3.9, an authenticated administrator can place crafted content in the applicationName setting through CSP nonce injection. The persistent injection is inserted into the main app…

  • Medium 5.4

    Cross-site Scripting (XSS) in Kendo UI for jQuery Calendar and MultiViewCalendar

    In Progress® Kendo® UI for jQuery prior to version 2026.3.1015, the Calendar and MultiViewCalendar month content templates render data.url and data.title without proper URL sanitization and HTML attribute encoding. An attacker with low privileges who can cont…

  • Medium 5.4

    Cross-site Scripting (XSS) in Kendo UI for jQuery Splitter, Window, and Tooltip

    In Progress® Kendo® UI for jQuery prior to 2026.3.1015, the Splitter and Window components starting with version 2011.2.804 and the Tooltip component starting with version 2013.1.319 construct iframe markup without properly sanitizing URL values or encoding t…

  • High 7.1

    WordPress Social Share Buttons plugin <= 1.31 - Cross Site Scripting (XSS) vulnerability

    Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in maxfoundry Social Share Buttons share-button allows Stored XSS.This issue affects Social Share Buttons: from n/a through 1.31.

  • High 7.1

    WordPress Link Whisper Free plugin <= 0.9.7 - Cross Site Scripting (XSS) vulnerability

    Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Link Whisper INC Link Whisper Free link-whisper allows Reflected XSS.This issue affects Link Whisper Free: from n/a through 0.9.7.

  • Medium 6.5

    WordPress User Registration plugin <= 5.2.8 - Cross Site Scripting (XSS) vulnerability

    Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in ThemeGrill User Registration user-registration allows Stored XSS.This issue affects User Registration: from n/a through 5.2.8.

  • High 7.1

    WordPress BSK PDF Manager plugin <= 3.8.1 - Cross Site Scripting (XSS) vulnerability

    Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in bannersky BSK PDF Manager bsk-pdf-manager allows Stored XSS.This issue affects BSK PDF Manager: from n/a through 3.8.1.

  • High 7.1

    WordPress Everest Forms plugin <= 3.6.1 - Cross Site Scripting (XSS) vulnerability

    Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Everest Forms Everest Forms everest-forms allows Stored XSS.This issue affects Everest Forms: from n/a through 3.6.1.

  • Medium 6.3

    Privilege Escalation via QuFTP Log-based XSS

    A cross-site scripting (XSS) vulnerability has been reported to affect QuFTP Service. If a remote attacker gains a user account, they can then exploit the vulnerability to inject malicious code. We have already fixed the vulnerability in the following version…

  • Medium 4.8

    Stored Cross-Site Scripting (XSS) in Note Station file upload functionality

    A cross-site scripting (XSS) vulnerability has been reported to affect Notes Station 3. If a remote attacker gains a user account, they can then exploit the vulnerability to inject malicious code. We have already fixed the vulnerability in the following versi…

  • Medium 6.2

    Stored XSS via Interface Name in Network & Virtual Switch App

    A cross-site scripting (XSS) vulnerability has been reported to affect Network & Virtual Switch. If a remote attacker gains an administrator account, they can then exploit the vulnerability to inject malicious code. We have already fixed the vulnerability in …

  • High 7.1

    Document Gallery <= 5.1.1 - Reflected XSS via data-shortcode Attribute

    The Document Gallery WordPress plugin through 5.1.1 does not properly sanitise and escape user input before reflecting it inside an HTML attribute in the response of an unauthenticated AJAX action, leading to a Reflected Cross-Site Scripting vulnerability whi…

  • Medium 6.1

    Tracking Code Manager <= 2.6.0 - Reflected Cross-Site Scripting via 'TCM_ErrorMessages'

    The Tracking Code Manager plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via 'TCM_ErrorMessages' POST Parameter in all versions up to, and including, 2.6.0 due to insufficient input sanitization and output escaping. This makes it possibl…

  • Medium 6.4

    VK Blocks <= 1.126.1 - Authenticated (Contributor+) Stored Cross-Site Scripting via Group Block 'linkToPost' Feature

    The VK Blocks plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Group Block 'linkToPost' Feature in all versions up to, and including, 1.126.1 due to insufficient input sanitization and output escaping. This makes it possible for authentic…

  • Medium 6.1

    Photo Gallery by 10Web <= 1.8.42 - Reflected Cross-Site Scripting via 'title' Parameter

    The Photo Gallery by 10Web – Mobile-Friendly Image Gallery plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'title' parameter in all versions up to, and including, 1.8.42 due to insufficient input sanitization and output escaping. …

  • High 7.2

    Groundhogg <= 4.5.14 - Unauthenticated Stored Cross-Site Scripting via 'ref' Parameter

    The Groundhogg — CRM, Newsletters, and Marketing Automation plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'ref' parameter in all versions up to, and including, 4.5.14 due to insufficient input sanitization and output escaping. This…

  • High 7.2

    Mang Board WP <= 2.4.0 - Unauthenticated Stored Cross-Site Scripting via 'data_type' Parameter

    The Mang Board WP plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'data_type' parameter in all versions up to, and including, 2.4.0 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticate…

  • High 7.2

    Premium Packages <= 7.0.5 - Unauthenticated Stored Cross-Site Scripting via 'order_email'

    The Premium Packages – Sell Digital Products Securely plugin for WordPress is vulnerable to Unauthenticated Stored Cross-Site Scripting via 'order_email' in all versions up to, and including, 7.0.5 due to insufficient input sanitization and output escaping. T…

  • Medium 6.4
    CVE-2026-17001 Public exploit

    Import and export users and customers <= 2.4.5 - Authenticated (Custom+) Stored Cross-Site Scripting via User Meta Profile Fields

    The Import and export users and customers plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Custom Column User Meta Profile Fields in all versions up to, and including, 2.4.5 due to insufficient input sanitization and output escaping. This…

  • Medium 6.4

    Post and Page Builder by BoldGrid <= 1.27.13 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'data-label' Attribute

    The Post and Page Builder by BoldGrid – Visual Drag and Drop Editor plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the Table Designer 'data-label' Attribute in all versions up to, and including, 1.27.13 due to insufficient input sanitiz…

  • Medium 6.4

    Kirki <= 6.2.0 - Authenticated (Custom+) Stored Cross-Site Scripting via Page Builder Text Content

    The Kirki – Freeform Page Builder, Website Builder & Customizer plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Page Builder Text Content in all versions up to, and including, 6.2.0 due to insufficient input sanitization and output escap…

  • Medium 6.1

    ELADMIN v2.7 and before is vulnerable to Cross Site Scripting (XSS) via the component WebSocketServer, SpringSecurityCo…

  • Medium 5.4

    XXL-JOB <=3.5.0-SNAPSHOT contains a stored Cross-Site Scripting (XSS) vulnerability in the job log list page (/joblog).…

  • Medium 5.4

    XXL-JOB through 3.5.0-SNAPSHOT is vulnerable to stored cross-site scripting (XSS) in the GLUE code editor. JobCodeContr…

  • High 7.2

    n8n before 1.123.83, 2.41.4, and 2.42.1 Stored XSS via Binary-Data File Preview

    n8n before 1.123.83, 2.41.4, and 2.42.1 contains a stored cross-site scripting vulnerability in the file-preview modal, which re-publishes binary data as an unsandboxed same-origin blob URL. A member who uploads a crafted item can run script in the n8n origin…

  • High 7.0

    n8n before 1.123.83, 2.41.4, and 2.42.1 Stored XSS via Chat Trigger customCss Parameter

    n8n before 1.123.83, 2.x before 2.41.4, and 2.42.x before 2.42.1 contains a stored cross-site scripting vulnerability in the Chat Trigger hosted-chat page, where insufficiently sanitised customCss values are interpolated into the page as markup. Workflow auth…

  • Medium 4.8

    FileRise: Unsanitized footerHtml in Public Site Config

    FileRise is a self-hosted web-based file manager with multi-file upload, editing, and batch operations. Prior to 3.21.0, FileRise returns the stored branding.footerHtml value through the unauthenticated public site configuration API without server-side saniti…

  • Low 0.4

    PAN-OS: Stored Cross-Site Scripting (XSS) Vulnerability

    A stored cross-site scripting (XSS) vulnerability in Palo Alto Networks PAN-OS® software enables a malicious authenticated administrator to store or execute a JavaScript payload using the web interface. The security risk posed by this issue is minimized when …