CVE-2026-95863
HighCVSS 7.6Summary
Apache Wicket generates JavaScript that references rendered elements, placing markup ids and form input names inside single-quoted JavaScript string literals without proper escaping. A value containing a single quote or backslash can terminate the literal and inject script that runs in the application's origin when the page loads. The issue affects wicket-core and wicket-extensions in versions 8.0.0 through 8.19.0, 9.0.0 through 9.24.0, and 10.0.0 through 10.11.0.
Risk Assessment
This cross-site scripting (XSS) vulnerability may allow execution of malicious script in a user's browser within the application's origin if a markup id or component id originates from application data and contains dangerous characters. The default Content-Security-Policy in Wicket 9.x and 10.x does not prevent this attack.
Recommendation
Upgrade Apache Wicket to version 8.20.0, 9.25.0, or 10.12.0, which validate ids at input and reject values containing dangerous characters. Users of the unsupported 7.x branch should migrate to a supported version.
Other vulnerabilities in Apache Wicket
See all- CVE-2026-87718Low
Apache Wicket 10.10.0, 10.11.0 and 9.24.0 do not set Content-Security-Policy headers on a page whose render request handler is wrapped in more than one IRequestHandlerDelegate. The framework unwraps only a single delegate level when deciding whether a request renders a page, so with a deeper chain, for example an application-provided delegating request mapper combined with CryptoMapper, the page is served without any CSP header even though CSP is enabled, and no error or warning is raised. The nonce-based protection Wicket applies to inline scripts and styles, together with any other CSP directives configured by the application, is thereby lost for those pages, exposing them to content injection the policy was meant to prevent. Applications on stock Wicket that do not wrap request handlers themselves are not affected. Versions before 10.10.0 and 9.24.0 handled nested delegates correctly.
- CVE-2026-84231High
A cross-site scripting (XSS) vulnerability in Apache Wicket arises from improper neutralization of input during web page generation. The ExternalLink component, when bound to a non-anchor element, concatenates the model URL into a JavaScript string literal in the onclick attribute without proper escaping, allowing script execution in the application's origin.
- CVE-2026-84177Medium
Apache Wicket has an incorrect behavior order: a file path is validated by PackageResourceGuard before the framework appends the style, variation and locale attributes. As a result, the file opened may differ from the file approved by the guard, allowing disclosure of HTML markup templates of components whose class names contain an underscore (e.g. Report_v2).
- CVE-2026-84172Medium
In Apache Wicket, PackageResourceGuard incorrectly allows component markup templates to be served as package resources when wicket-core is loaded by a class loader that cannot see the application's classes. In such a setup the check for a class file beside the template fails, and a request for the package resource URL returns the component's markup template with status 200. Disclosed content is developer-authored template material such as component structure, comments, inline script, and named endpoints.
- CVE-2026-84170High
A vulnerability in Apache Wicket affects AbstractFileUploadResource, the server side of the form-less upload offered by FileUploadToResourceField. The request size, single-part size and part-count limits are taken from request parameters (maxSize, fileMaxSize, fileCountMax) instead of application configuration, so a client can raise or omit them. The resource carries no authorization annotation, so by default requests need no authentication.
- CVE-2026-83594High
A vulnerability in Apache Wicket affects the FileUploadToResourceField component, whose Ajax callback reads the filesInfo request parameter without binding it to an actual upload. The UploadInfo#get() method allocates a byte array based on the client-supplied size, allowing a single request to exhaust the JVM heap, while negative values trigger a NegativeArraySizeException.
- CVE-2026-83559High
A vulnerability in Apache Wicket affects the JavaScriptUtils#escapeQuotes() method, which fails to escape the backslash character before quotes. A value containing a backslash immediately before a quote results in the quote being left unescaped, closing the JavaScript string literal and allowing JavaScript injection. The issue occurs when an application uses this method to place attacker-influenced data inside a JavaScript string literal, including via the AjaxEditableLabel component.
- CVE-2026-83539High
Cross-site scripting (XSS) vulnerability in the SmartLinkLabel and SmartLinkMultiLineLabel components of Apache Wicket. These components turn URLs found in text into hyperlinks and accept any URL scheme, including script-executing schemes such as javascript:. Escaping the model value does not help because the payload ends up in the href attribute rather than in element text.
- CVE-2026-82956High
A cross-site scripting (XSS) vulnerability in Apache Wicket affects the AjaxNewWindowNotifyingBehavior, which stores the client-supplied window.name value in the page's serialized state. That value is later substituted without escaping into a single-quoted JavaScript string literal in the Ajax call precondition, allowing arbitrary script execution in the application's origin on every render of the page instance. Only applications that explicitly add this behavior to a component are affected.
- CVE-2026-111089High
Apache Wicket writes texts from resource bundles (labels, CSS class names) into generated JavaScript and markup without context-appropriate escaping. A text containing a quote can terminate the literal or attribute and be parsed as script or markup in the application's origin. Affected components include MultiFileUploadField, Form, UploadProgressBar, FilterForm and TrapFocusBehavior in versions 8.0.0–8.19.0, 9.0.0–9.24.0 and 10.0.0–10.11.0.
Original NVD description (English source)
Improper neutralization of input during web page generation in Apache Wicket. Apache Wicket generates JavaScript that refers to the elements it renders, and writes into that JavaScript two values it derives itself: a component's markup id, and the input name of a form component, which is built from component ids. Both are placed inside single-quoted JavaScript string literals without being escaped for that context, so a value containing a single quote or a backslash ends the literal, and what follows is parsed as script and runs in the application's origin when the page loads. A markup id is the value passed to org.apache.wicket.Component#setMarkupId(String), or the id attribute written in the component's markup, or an id Wicket generates, in that order. The first two are supplied by the application in an HTML context, where both characters are legal and where Wicket escapes them correctly when it writes the same value into the id attribute of the element; a generated id cannot contain either. An input name is derived from the ids of the components between the form and the form component, and a component id was rejected only for ':' and '~'. In org.apache.wicket:wicket-core on 9.x and 10.x, org.apache.wicket.markup.head.OnEventHeaderItem#forMarkupId(String, String, CharSequence) quotes the id it is given into a Wicket.Event.add call, and components in both wicket-core and wicket-extensions reach it through #forComponent(Component, String, CharSequence). On every affected version, org.apache.wicket.markup.html.form.Form writes its markup id and the id of its hidden-fields container into such literals, org.apache.wicket.markup.html.form.FormComponentUpdatingBehavior writes an input name, and org.apache.wicket.markup.html.form.upload.MultiFileUploadField writes two markup ids and an input name. On 8.x, Form also writes an input name into the action of a submitting link, and on 8.x and 9.x Form#appendDefaultButtonField writes an input name into a name attribute with no escaping at all, so a value containing a double quote escapes the attribute into markup. org.apache.wicket:wicket-extensions is affected in its own right and not only through wicket-core: AjaxEditableLabel, AjaxIndicatorAppender, AjaxDisableComponentListener, UploadProgressBar, KittenCaptchaPanel, Palette, FilterForm and, on 9.x and 10.x, TrapFocusBehavior and AjaxListPanel each build their own JavaScript containing a markup id. An application is affected where a markup id or a component id carries one of those characters. Wicket does not put one there itself, so the value comes from the application: an id set on a component, an id attribute in a template, or a component id derived from data. None of those is a JavaScript context from the application's point of view. The Content-Security-Policy that Apache Wicket 9.x and 10.x send by default does not prevent this. The generated script is written into a script element carrying the per-response nonce, so the injected code is part of a script the policy admits. The fixed versions check an id where it enters instead of escaping each place it is written. A component id and a markup id may no longer contain a quote, a backquote, a backslash, braces, angle brackets, a semicolon, an ampersand or a control character, and a markup id may not contain parentheses or square brackets either; a component constructed with such an id, or given such a markup id, fails with an exception. This issue affects Apache Wicket: from 8.0.0 through 8.19.0, from 9.0.0 through 9.24.0, from 10.0.0 through 10.11.0. Users of Apache Wicket 7.x or older, which are no longer supported, should upgrade to a supported version. Users are recommended to upgrade to version 8.20.0, 9.25.0 or 10.12.0, which fix the issue.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS