CVE-2026-95863
Received
Received - Intake
Cross-Site Scripting in Apache Wicket
Vulnerability report for CVE-2026-95863, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-11-01
Last updated on: 2026-11-01
Assigner: Apache Software Foundation
Description
Description
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.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| Apache Software Foundation | Apache Wicket | 8.0.0 |
| Apache Software Foundation | Apache Wicket | 9.0.0 |
| Apache Software Foundation | Apache Wicket | 10.0.0 |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-79 | 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. |
