Applying the following changes to undertow addresses this: undertow$ git diff diff --git a/core/src/main/java/io/undertow/server/handlers/resource/FileResourceManager.java b/core/src/main/java/io/undertow/server/handlers/resource/FileResourceManager.java --- a/core/src/main/java/io/undertow/server/handlers/resource/FileResourceManager.java +++ b/core/src/main/java/io/undertow/server/handlers/resource/FileResourceManager.java @@ -135,6 +135,8 @@ public class FileResourceManager implements ResourceManager { if (path.endsWith( "/" ) && ! file.isDirectory()) { //UNDERTOW-432 don't return non directories if the path ends with a / return null ; + } else if (path.endsWith( "." )) { + return null ; } boolean isSymlinkPath = isSymlinkPath(base, file); if (isSymlinkPath) { diff --git a/core/src/main/java/io/undertow/server/handlers/resource/ResourceHandler.java b/core/src/main/java/io/undertow/server/handlers/resource/ResourceHandler.java --- a/core/src/main/java/io/undertow/server/handlers/resource/ResourceHandler.java +++ b/core/src/main/java/io/undertow/server/handlers/resource/ResourceHandler.java @@ -208,6 +208,10 @@ public class ResourceHandler implements HttpHandler { exchange.setResponseCode(404); exchange.endExchange(); return ; + } else if (exchange.getRelativePath().endsWith( "." )) { + exchange.setResponseCode(404); + exchange.endExchange(); + return ; } final ETag etag = resource.getETag(); diff --git a/servlet/src/main/java/io/undertow/servlet/handlers/DefaultServlet.java b/servlet/src/main/java/io/undertow/servlet/handlers/DefaultServlet.java --- a/servlet/src/main/java/io/undertow/servlet/handlers/DefaultServlet.java +++ b/servlet/src/main/java/io/undertow/servlet/handlers/DefaultServlet.java @@ -172,6 +172,9 @@ public class DefaultServlet extends HttpServlet { //UNDERTOW-432 resp.sendError(404); return ; + } else if (path.endsWith( "." )) { + resp.sendError(404); + return ; } serveFileBlocking(req, resp, resource); } Note the similarity that this workaround shares with the resolution of WFLY-4595 (which was implemented by commit 4c330e2ac8a3694bfc6196e7b38ba8a426f96f8c of the 1.2.x branch of the git repository ssh://git@github.com/undertow-io/undertow where it has been called UNDERTOW-432). This workaround does however forbid any serving of files that actually have a period in the end of file name, why this is perhaps not a solution but only a workaround.