GHSA-m394-8rww-3jr7

DOS vulnerability for Quoted Quality CSV headers

### Impact When Jetty handles a request containing request headers with a large number of “quality” (i.e. q) parameters (such as what are seen on the `Accept`, `Accept-Encoding`, and `Accept-Language` request headers), the server may enter a denial of service (DoS) state due to high CPU usage while sorting the list of values based on their quality values. A single request can easily consume minutes of CPU time before it is even dispatched to the application. The only features within Jetty that can trigger this behavior are: - Default Error Handling - the `Accept` request header with the `QuotedQualityCSV` is used to determine what kind of content to send back to the client (html, text, json, xml, etc) - `StatisticsServlet` - uses the `Accept` request header with the `QuotedQualityCSV` to determine what kind of content to send back to the client (xml, json, text, html, etc) - `HttpServletRequest.getLocale()` - uses the `Accept-Language` request header with the `QuotedQualityCSV` to determine which “preferred” language is returned on this call. - `HttpservletRequest.getLocales()` - is similar to the above, but returns an ordered list of locales based on the quality values on the `Accept-Language` request header. - `DefaultServlet` - uses the `Accept-Encoding` request header with the `QuotedQualityCSV` to determine which kind of pre-compressed content should be sent back for static content (content that is not matched against a url-pattern in your web app) ### Versions `QuotedQualityCSV` was introduced to Jetty 9.3.9.v20160517 and the bug that introduced the vulnerability was in 9.4.6.v20170531. Currently, known vulnerable versions include: - 9.4.6.v20170531 thru to 9.4.36.v20210114 - 10.0.0 - 11.0.0 ### Workarounds Quality ordered values are used infrequently by jetty so they can be avoided by: * Do not use the default error page/handler. * Do not deploy the `StatisticsServlet` exposed to the network * Do not call `getLocale` API * Do not enable precompressed static content in the `DefaultServlet` ### Patches All patches are available for download from the Eclipse Jetty website at [https://www.eclipse.org/jetty/download.php](https://www.eclipse.org/jetty/download.php) - 9.4.37.v20210219 and greater - 10.0.1 and greater - 11.0.1 and greater