Multiple vulnerabilities in nginx as packaged for various Ubuntu LTS releases allow remote attackers to cause denial of service or potentially execute arbitrary code. These include improper handling of alias directives with rewrite rules, map directives using regex matching, HTTP/3 requests with proxy_request_buffering enabled, asynchronous file I/O with Server Side Includes, and SSL session ticket key management. The issues affect Ubuntu 14.04 LTS through 20.04 LTS and have been fixed in updated package versions.