CVE-2026-84177: Incorrect behavior order in Apache Wicket: a file path is validated before the framework appends the attributes that complete it.

Incorrect behavior order in Apache Wicket: a file path is validated before the framework appends the attributes that complete it.

Incorrect behavior order in Apache Wicket: a file path is validated before the framework appends the attributes that complete it. org.apache.wicket.request.resource.PackageResource asks the configured package resource guard about a path built from the scope class' package and the file name in the request URL, and then hands that same path to the resource stream locator together with a style, a variation and a locale. Those three attributes are decoded from the name of the first query parameter and never appear in the string the guard was given. org.apache.wicket.core.util.resource.locator.ResourceNameIterator appends them to that path, each preceded by an underscore, in the order variation, style, locale, before the file extension, so the file that is opened is not the file the guard approved. org.apache.wicket.markup.html.PackageResourceGuard decides whether an HTML file is a component's markup template by looking for a class file of the same name beside it, stripping one underscore-delimited suffix at a time as it goes. HTML is on the default allow list, so that check is the only thing separating a static HTML file, which may be served, from a markup template, which may not. As

Description from the National Vulnerability Database, published by security@apache.org

What it means for a small business

Apache Wicket runs on web servers, so this is mostly your hosting company's to fix. On shared hosting you can't patch it yourself, but you can ask.

Ask your host whether your server runs it, whether it's updated, and on what date. A good host answers that in a day.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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