vertx-core: Eclipse Vert.x: Information disclosure via improper handling of HTTP 30x redirects

In Eclipse Vert.x versions up to and including 4.5.29 (4.x branch) and 5.1.4 (5.x branch), DefaultRedirectHandler (vertx-core) propagates all request headers as-is across cross-origin HTTP 30x redirects. Only Content-Length is stripped; no origin comparison (scheme, host, port) is performed before copying headers to the redirect target. As a result, credential headers, including Authorization, Cookie, Proxy-Authorization, and arbitrary custom headers such as X-API-Token, are forwarded to the redirect destination without the caller's knowledge. An attacker who can cause a Vert.x HttpClient to issue a request that is redirected to an attacker-controlled host (for example, by supplying a URL to a webhook dispatcher, image proxy, or microservice URL fetcher) can capture bearer tokens, basic-auth credentials, session cookies, and API keys attached to the original request.

A TCP client can perform a TLS handshake and present the server name extension with a server name that is accepted by a server wildcard name, e.g. if the server is configured with a certificate accepting *.example.com, any XYZ.example.com where xyz is a valid name can be used.

Eclipse Vert.x Web static handler file access denial

The Vert.x Web static handler component cache can be manipulated to deny the access to static files served by the handler using specifically crafted request URI. The issue comes from an improper implementation of the C. rule of section 5.2.4 of RFC3986 and is fixed in Vert.x Core component (used by Vert.x Web): https://github.com/eclipse-vertx/vert.x/pull/5895 Steps to reproduce Given a file served by the static handler, craft an URI that introduces a string like bar%2F..%2F after the last / char to deny the access to the URI with an HTTP 404 response. For example https://example.com/foo/index.html can be denied with https://example.com/foo/bar%2F..%2Findex.html Mitgation Disabling Static Handler cache fixes the issue. StaticHandler staticHandler = StaticHandler.create().setCachingEnabled(false);

io.vertx/vertx-web: Eclipse Vert.x cross site scripting

In Eclipse Vert.x versions [4.0.0, 4.5.21] and [5.0.0, 5.0.4], when "directory listing" is enabled, file and directory names are inserted into generated HTML without proper escaping in the href, title, and link attributes. An attacker who can create or rename files or directories within a served path can craft filenames containing malicious script or HTML content, leading to stored cross-site scripting (XSS) that executes in the context of users viewing the affected directory listing.

io.vertx/vertx-core: Eclipse Vert.x Access Control Flaw

In Eclipse Vert.x versions [4.0.0, 4.5.21] and [5.0.0, 5.0.4], a StaticHandler configuration for restricting access to hidden files fails to restrict access to hidden directories, allowing unauthorized users to retrieve files within them (e.g. '.git/config').

Disclosure of classpath resources on Windows when mounted on a wildcard route in vertx-web

Vert.x-Web is a set of building blocks for building web applications in the java programming language. When running vertx web applications that serve files using `StaticHandler` on Windows Operating Systems and Windows File Systems, if the mount point is a wildcard (`*`) then an attacker can exfiltrate any class path resource. When computing the relative path to locate the resource, in case of wildcards, the code: `return "/" + rest;` from `Utils.java` returns the user input (without validation) as the segment to lookup. Even though checks are performed to avoid escaping the sandbox, given that the input was not sanitized `\` are not properly handled and an attacker can build a path that is valid within the classpath. This issue only affects users deploying in windows environments and upgrading is the advised remediation path. There are no known workarounds for this vulnerability.

Vert.x STOMP server process client frames that would not send initially a connect frame

Vert.x STOMP is a vert.x implementation of the STOMP specification that provides a STOMP server and client. From versions 3.1.0 until 3.9.16 and 4.0.0 until 4.4.2, a Vert.x STOMP server processes client STOMP frames without checking that the client send an initial CONNECT frame replied with a successful CONNECTED frame. The client can subscribe to a destination or publish message without prior authentication. Any Vert.x STOMP server configured with an authentication handler is impacted. The issue is patched in Vert.x 3.9.16 and 4.4.2. There are no trivial workarounds.

vertx-web: performs an incorrect CSRF verification

Vert.x-Web framework v4.0 milestone 1-4 does not perform a correct CSRF verification. Instead of comparing the CSRF token in the request with the CSRF token in the cookie, it compares the CSRF token in the cookie against a CSRF token that is stored in the session. An attacker does not even need to provide a CSRF token in the request because the framework does not consider it. The cookies are automatically sent by the browser and the verification will always succeed, leading to a successful CSRF attack.

In Eclipse Vert.x 3.4.x up to 3.9.4, 4.0.0.milestone1, 4.0.0.milestone2, 4.0.0.milestone3, 4.0.0.milestone4, 4.0.0.milestone5, 4.0.0.Beta1, 4.0.0.Beta2, and 4.0.0.Beta3, StaticHandler doesn't correctly processes back slashes on Windows Operating systems, allowing, escape the webroot folder to the current working directory.

vertx: API Validation XML Schemas do not forbid file system access

In version from 3.5.Beta1 to 3.5.3 of Eclipse Vert.x, the OpenAPI XML type validator creates XML parsers without taking appropriate defense against XML attacks. This mechanism is exclusively when the developer uses the Eclipse Vert.x OpenAPI XML type validator to validate a provided schema.

In version from 3.0.0 to 3.5.3 of Eclipse Vert.x, the StaticHandler uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize '\' (forward slashes) sequences that can resolve to a location that is outside of that directory when running on Windows Operating Systems.

vertx: WebSocket HTTP upgrade implementation holds the entire http request in memory before the handshake

In version from 3.0.0 to 3.5.3 of Eclipse Vert.x, the WebSocket HTTP upgrade implementation buffers the full http request before doing the handshake, holding the entire request body in memory. There should be a reasonnable limit (8192 bytes) above which the WebSocket gets an HTTP response with the 413 status code and the connection gets closed.

vertx-web: Incomplete CSRF validation by CSRFHandler

In version from 3.0.0 to 3.5.2 of Eclipse Vert.x, the CSRFHandler do not assert that the XSRF Cookie matches the returned XSRF header/form parameter. This allows replay attacks with previously issued tokens which are not expired yet.

vertx: Improper neutralization of CRLF sequences allows remote attackers to inject arbitrary HTTP response headers

In Eclipse Vert.x version 3.0 to 3.5.1, the HttpServer response headers and HttpClient request headers do not filter carriage return and line feed characters from the header value. This allow unfiltered values to inject a new header in the client request or server response.

Eclipse Vert.x gRPC server does not limit the maximum message size

In Eclipse Vert.x version 4.3.0 to 4.5.9, the gRPC server does not limit the maximum length of message payload (Maven GAV: io.vertx:vertx-grpc-server and io.vertx:vertx-grpc-client).  This is fixed in the 4.5.10 version.  Note this does not affect the Vert.x gRPC server based grpc-java and Netty libraries (Maven GAV: io.vertx:vertx-grpc)