Security Vulnerabilities
Improper neutralization of input during web page generation in Apache Wicket.
The <wicket:label> tag is provided by org.apache.wicket.markup.html.form.AutoLabelTextResolver, which is registered by default in every WebApplication. The resolver writes the label it finds into the markup as it is, and reads no escaping setting at all, so markup in a label is rendered as markup.
When the label comes from the labelled component's label model, set through FormComponent#setLabel(IModel), it is written to the markup unescaped. An application is affected where the label of a form component holds data an attacker can influence. Wicket cannot determine where a model value comes from, so whether it reaches the page from a request or from storage is a property of the application.
There is no workaround. Unlike every other rendering path in Wicket, the resolver never consulted the escape-model-strings setting, so an application had no way to ask for the label to be escaped.
The body of a <wicket:label> tag is markup by design and is not affected; it remains the supported way to place markup in a label.
This issue affects Apache Wicket: from 8.0.0 through 8.18.0, from 9.0.0 through 9.23.0, from 10.0.0 through 10.10.0. Older, unsupported releases from 1.5.0 onwards are also affected. Users are recommended to upgrade to version 8.19.0, 9.24.0 or 10.11.0, which fix the issue.
CVSS Score
5.1
EPSS Score
0.004
Published
2026-08-31
Improper neutralization of input during web page generation in Apache Wicket.
org.apache.wicket.markup.head.MetaDataHeaderItem generates <meta> and <link> header tags. It escaped the attribute names it wrote, but ran the attribute values through a replacement of " with \". A backslash before a double quote means nothing in HTML, so a value containing a double quote ends its own attribute and what follows is parsed as further attributes of the generated tag.
An application is affected where it supplies an attribute value holding data an attacker can influence, through addTagAttribute or the forMetaTag and forLinkTag factory methods. A value may be given as an IModel, so it is not necessarily a literal.
There is no setting to change; an application can only avoid supplying a value that contains a double quote. Note that these values have never been escaped effectively: before the change released in 6.24.0, 7.4.0 and 8.0.0 they were written with no escaping at all.
This issue affects Apache Wicket: from 8.0.0 through 8.18.0, from 9.0.0 through 9.23.0, from 10.0.0 through 10.10.0. Older, unsupported releases from 6.17.0 onwards are also affected. Users are recommended to upgrade to version 8.19.0, 9.24.0 or 10.11.0, which fix the issue.
CVSS Score
5.1
EPSS Score
0.004
Published
2026-08-31
Improper validation of resource URL attributes in Apache Wicket allows an unauthenticated remote attacker to read files from the web application, including files under WEB-INF that the servlet container would not otherwise serve.
The locale, style and variation attributes decoded from a package resource URL are spliced into the resource lookup path without being checked for path separators. The IPackageResourceGuard — whose rejection of .. is one of the two intended controls — is applied to the resource name before those attributes are appended, and WebApplicationPath rejects only paths literally beginning with WEB-INF/. Neither control ever inspects the attacker-controlled portion of the path. On servlet containers that normalize .. in ServletContext.getResource(), a crafted request therefore escapes the intended package directory.
The set of readable files is limited to the file extensions permitted by the configured IPackageResourceGuard. The default SecurePackageResourceGuard permits only js, css, png, jpg, jpeg, gif, ico, cur, map, html, txt, swf, bmp, svg, avif, eot, ttf, woff and woff2, which excludes configuration formats. Applications that have added patterns to the guard, or replaced it with the blocklist-based PackageResourceGuard, can additionally disclose configuration files such as web.xml. Independently of the extension, the lookup performed before the guard runs acts as an existence oracle for arbitrary paths.
This issue affects Apache Wicket 8.18.0 and before, 9.23.0 and before and 10.10.0 and before.
Users are recommended to upgrade to version 8.19.0, 9.24.0 or 10.11.0, which fix the issue. Users of Apache Wicket 7.x or older, which are no longer supported, should upgrade to a supported version.
CVSS Score
5.3
EPSS Score
0.005
Published
2026-08-31
Apache Wicket enforces the upload limits configured on a form or upload field while parsing a multipart request with Apache Commons FileUpload. If the request body has already been consumed by another component, Commons FileUpload returns no items and Wicket falls back to reading the upload through HttpServletRequest#getParts(). The per-file size limit (for example Form#setFileMaxSize) and the file count limit (Form#setFileCountMax) are not applied to the parts obtained that way, and no exception is raised, so the upload is processed as though those limits had been satisfied. A remote uploader can therefore submit files that are larger, or more numerous, than the application permits, up to whatever the component that parsed the request allows. A part carrying no Content-Type header is additionally read into memory in full during parsing, so the size of that allocation is determined by the request and bounded only by those same external limits.
The total upload size limit (Form#setMaxSize) is not affected. Commons FileUpload compares the declared Content-Length against it before reading the body, so a request declaring an oversized length is rejected before the fallback is reached.
The fallback is reached in deployments where a servlet or filter has already parsed the request body — for example a servlet annotated with @MultipartConfig, Spring Boot's multipart resolver, or any filter that calls HttpServletRequest#getParameter() on a multipart request. It applies to the Wicket components that accept uploads on that path, including Form with FileUploadField, FileUploadToResourceField and AjaxFileDropBehavior. Applications that configure neither a per-file nor a file-count limit are not affected, as Wicket applies neither by default.
This issue affects Apache Wicket: from 8.0.0 through 8.18.0, from 9.0.0 through 9.23.0, from 10.0.0 through 10.10.0.
Users are recommended to upgrade to version 8.19.0, 9.24.0 or 10.11.0, which fix the issue. Users of Apache Wicket 7.x or older, which are no longer supported, should upgrade to a supported version. As a workaround, configure equivalent limits in the component that parses the request — for example spring.servlet.multipart.max-file-size and max-request-size, or maxFileSize and maxRequestSize in @MultipartConfig or in the web.xml <multipart-config> element.
CVSS Score
7.5
EPSS Score
0.002
Published
2026-08-31
ResourceIsolationRequestCycleListener protects a Wicket application against cross-site request forgery by rejecting requests that a resource isolation policy judges to come from another origin. Its default policy, FetchMetadataResourceIsolationPolicy, was derived from a reference implementation written to guard static resources, and it inherited two allowances that are unsafe when the thing being guarded is an action on a page:
* Every "simple top-level navigation" was allowed. Any GET request carrying Sec-Fetch-Mode: navigate whose Sec-Fetch-Dest was neither object nor embed was allowed, whatever Sec-Fetch-Site said — including cross-site. Wicket invokes component listeners (Link.onClick(), form submits, behaviour callbacks) through ordinary GET navigations, so a page under an attacker's control could navigate the victim's browser to a listener URL and have that listener run inside the victim's authenticated session. Browsers send SameSite=Lax cookies — the effective default when no SameSite attribute is set — on cross-site top-level GET navigations, so the victim's session cookie accompanied the request.
* Sec-Fetch-Site: same-site was allowed unconditionally. That value means the same registrable domain and scheme but a different origin — another subdomain or another port. Any sibling origin could therefore invoke any listener by any method, POST form submits included, and cookies are always sent on same-site requests regardless of SameSite. A hostile sibling origin obtained through a subdomain takeover, through delegated user content, or through an XSS elsewhere on the site could act as the authenticated user.
Users are recommended to upgrade to version 9.24.0 or 10.11.0, which fix the issue.
Affected versions
* Apache Wicket 9.1.0 through 9.23.0
* Apache Wicket 10.0.0 through 10.10.0
Not affected
Any release older than 9.1.0:
* Apache Wicket 8.x (8.0.0 through 8.17.0). The resource isolation classes do not exist in the 8.x line, which offers only the Origin/Referer-based CsrfPreventionRequestCycleListener. No 8.x release requires a fix.
* Apache Wicket 9.0.0. ResourceIsolationRequestCycleListener and FetchMetadataResourceIsolationPolicy were introduced by WICKET-6786 and first shipped in 9.1.0 (released 2020-10-07).
CVSS Score
4.6
EPSS Score
0.001
Published
2026-08-31
AjaxEditableChoiceLabel in wicket-extensions, when constructed with a non-null IChoiceRenderer, writes the display value obtained from that renderer into the label's markup without applying the HTML escaping Wicket performs by default for component model values. An attacker who can influence the choice or model data rendered by such a label can inject HTML or script that executes in the browser of any user who views the page. The same value is correctly escaped when the component's dropdown editor renders it as an option, so only the label rendering is affected.
AjaxEditableLabel, AjaxEditableChoiceLabel and AjaxEditableMultiLineLabel write the value returned by the protected defaultNullLabel() method into the label's markup the same way when the component's model is empty, while the model value they show otherwise is escaped. The default implementation returns a constant, so an application is affected where it overrides that method and returns a value an attacker can influence.
Neither value could be escaped by configuration, because escapeModelStrings had no effect on any of the three components: it is read by the label they render with rather than by the component itself, and nothing carried the setting across.
This issue affects Apache Wicket: from 8.0.0 through 8.18.0, from 9.0.0 through 9.23.0, from 10.0.0 through 10.10.0. Older, unsupported releases are also affected; the display value from the renderer since 6.22.0 and the null label since 1.4.0. Users are recommended to upgrade to version 8.19.0, 9.24.0 or 10.11.0, which fix the issue.
CVSS Score
5.1
EPSS Score
0.004
Published
2026-08-31
When Apache Shiro is used with the Jakarta EE integration module, a low-privileged user can craft an HTTP request that causes the server to initiate a connection to an attacker-controlled URL and transmit attacker-controlled data. This vulnerability affects Apache Shiro versions 2.x through 3.0.0 only in deployments that use the Jakarta EE integration module.
Mitigation: Upgrade to version 3.0.1 or later, which fixes the issue. +
Alternatively, you can set the `org.apache.shiro.form-resubmit-host` (String) and `org.apache.shiro.form-resubmit-port` (Integer) system properties to restrict the host and port that Shiro will connect to when resubmitting a form.
CVSS Score
5.9
EPSS Score
0.002
Published
2026-08-31
multer is a middleware for handling multipart/form-data in Node.js. A small multipart request with two specially crafted text field names can make multer's field parser synchronously iterate a maximum-length sparse array, blocking the event loop so the process cannot handle other requests. A large numeric array index in the first field allocates a maximum-length sparse array, and a second field with a non-numeric key then triggers a full-length iteration inside the append-field dependency. All versions before 2.3.0 are affected, and this is a remotely triggerable denial of service. multer 2.3.0 adds an opt-in fieldArrayIndexLimit option that rejects oversized array indexes. Upgrade to multer 2.3.0 and set limits.fieldArrayIndexLimit to the largest array index your application needs to remediate.
CVSS Score
7.5
EPSS Score
0.003
Published
2026-08-28
multer is a middleware for handling multipart/form-data in Node.js. In version 2.2.0, when a disk-backed upload is aborted or truncated before the write stream finishes, multer's disk storage engine removes the visible file but does not close the underlying write file descriptor, leaving a deleted but still open descriptor. A remote attacker able to reach an upload route using the built-in disk storage can send repeated aborted or malformed multipart uploads, each one leaking a file descriptor and retaining disk blocks until the process exits, which can exhaust resources and cause a denial of service. The issue is fixed in multer 2.3.0, which closes the destination write stream on abnormal source termination and defers cleanup until the stream has closed. Upgrade to multer 2.3.0 to remediate.
CVSS Score
7.5
EPSS Score
0.003
Published
2026-08-28
multer is a middleware for handling multipart/form-data in Node.js. When an application uses an asynchronous fileFilter together with the fileSize limit, a race condition in multer's file stream handling can allow a file that exceeds the configured size limit to bypass the size-limit rejection. All versions before 2.3.0 are affected. The impact is limited because the underlying multipart parser still truncates the stream at the size limit, so this is a bypass of the limit rejection rather than uncontrolled resource consumption. The issue is fixed in multer 2.3.0. Upgrade to multer 2.3.0 to remediate.
CVSS Score
3.7
EPSS Score
0.002
Published
2026-08-28