There exists a security vulnerability in Jetty's ThreadLimitHandler.getRemote() which can be exploited by unauthorized users to cause remote denial-of-service (DoS) attack. By repeatedly sending crafted requests, attackers can trigger OutofMemory errors and exhaust the server's memory.

Eclipse Jetty is a lightweight, highly scalable, Java-based web server and Servlet engine . It includes a utility class, HttpURI, for URI/URL parsing. The HttpURI class does insufficient validation on the authority segment of a URI. However the behaviour of HttpURI differs from the common browsers in how it handles a URI that would be considered invalid if fully validated against the RRC. Specifically HttpURI and the browser may differ on the value of the host extracted from an invalid URI and thus a combination of Jetty and a vulnerable browser may be vulnerable to a open redirect attack or to a SSRF attack if the URI is used after passing validation checks.

Eclipse Jetty provides a web server and servlet container. In versions 11.0.0 through 11.0.15, 10.0.0 through 10.0.15, and 9.0.0 through 9.4.52, an integer overflow in `MetaDataBuilder.checkSize` allows for HTTP/2 HPACK header values to exceed their size limit. `MetaDataBuilder.java` determines if a header name or value exceeds the size limit, and throws an exception if the limit is exceeded. However, when length is very large and huffman is true, the multiplication by 4 in line 295 will overflow, and length will become negative. `(_size+length)` will now be negative, and the check on line 296 will not be triggered. Furthermore, `MetaDataBuilder.checkSize` allows for user-entered HPACK header value sizes to be negative, potentially leading to a very large buffer allocation later on when the user-entered size is multiplied by 2. This means that if a user provides a negative length value (or, more precisely, a length value which, when multiplied by the 4/3 fudge factor, is negative), and this length value is a very large positive number when multiplied by 2, then the user can cause a very large buffer to be allocated on the server. Users of HTTP/2 can be impacted by a remote denial of service attack. The issue has been fixed in versions 11.0.16, 10.0.16, and 9.4.53. There are no known workarounds.

The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can reset many streams quickly, as exploited in the wild in August through October 2023.

Jetty is a Java based web server and servlet engine. Versions 9.4.21 through 9.4.51, 10.0.15, and 11.0.15 are vulnerable to weak authentication. If a Jetty `OpenIdAuthenticator` uses the optional nested `LoginService`, and that `LoginService` decides to revoke an already authenticated user, then the current request will still treat the user as authenticated. The authentication is then cleared from the session and subsequent requests will not be treated as authenticated. So a request on a previously authenticated session could be allowed to bypass authentication after it had been rejected by the `LoginService`. This impacts usages of the jetty-openid which have configured a nested `LoginService` and where that `LoginService` will is capable of rejecting previously authenticated users. Versions 9.4.52, 10.0.16, and 11.0.16 have a patch for this issue.

Jetty is a Java based web server and servlet engine. Prior to versions 9.4.52, 10.0.16, 11.0.16, and 12.0.1, Jetty accepts the `+` character proceeding the content-length value in a HTTP/1 header field. This is more permissive than allowed by the RFC and other servers routinely reject such requests with 400 responses. There is no known exploit scenario, but it is conceivable that request smuggling could result if jetty is used in combination with a server that does not close the connection after sending such a 400 response. Versions 9.4.52, 10.0.16, 11.0.16, and 12.0.1 contain a patch for this issue. There is no workaround as there is no known exploit scenario.

Eclipse Jetty Canonical Repository is the canonical repository for the Jetty project. Users of the CgiServlet with a very specific command structure may have the wrong command executed. If a user sends a request to a org.eclipse.jetty.servlets.CGI Servlet for a binary with a space in its name, the servlet will escape the command by wrapping it in quotation marks. This wrapped command, plus an optional command prefix, will then be executed through a call to Runtime.exec. If the original binary name provided by the user contains a quotation mark followed by a space, the resulting command line will contain multiple tokens instead of one. This issue was patched in version 9.4.52, 10.0.16, 11.0.16 and 12.0.0-beta2.

Jetty is a java based web server and servlet engine. Nonstandard cookie parsing in Jetty may allow an attacker to smuggle cookies within other cookies, or otherwise perform unintended behavior by tampering with the cookie parsing mechanism. If Jetty sees a cookie VALUE that starts with `"` (double quote), it will continue to read the cookie string until it sees a closing quote -- even if a semicolon is encountered. So, a cookie header such as: `DISPLAY_LANGUAGE="b; JSESSIONID=1337; c=d"` will be parsed as one cookie, with the name DISPLAY_LANGUAGE and a value of b; JSESSIONID=1337; c=d instead of 3 separate cookies. This has security implications because if, say, JSESSIONID is an HttpOnly cookie, and the DISPLAY_LANGUAGE cookie value is rendered on the page, an attacker can smuggle the JSESSIONID cookie into the DISPLAY_LANGUAGE cookie and thereby exfiltrate it. This is significant when an intermediary is enacting some policy based on cookies, so a smuggled cookie can bypass that policy yet still be seen by the Jetty server or its logging system. This issue has been addressed in versions 9.4.51, 10.0.14, 11.0.14, and 12.0.0.beta0 and users are advised to upgrade. There are no known workarounds for this issue.

Jetty is a java based web server and servlet engine. In affected versions servlets with multipart support (e.g. annotated with `@MultipartConfig`) that call `HttpServletRequest.getParameter()` or `HttpServletRequest.getParts()` may cause `OutOfMemoryError` when the client sends a multipart request with a part that has a name but no filename and very large content. This happens even with the default settings of `fileSizeThreshold=0` which should stream the whole part content to disk. An attacker client may send a large multipart request and cause the server to throw `OutOfMemoryError`. However, the server may be able to recover after the `OutOfMemoryError` and continue its service -- although it may take some time. This issue has been patched in versions 9.4.51, 10.0.14, and 11.0.14. Users are advised to upgrade. Users unable to upgrade may set the multipart parameter `maxRequestSize` which must be set to a non-negative value, so the whole multipart content is limited (although still read into memory).