========================================================================== Ubuntu Security Notice USN-5090-2 September 27, 2021 apache2 vulnerabilities ========================================================================== A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 16.04 ESM - Ubuntu 14.04 ESM Summary: Several security issues were fixed in Apache HTTP Server. Software Description: - apache2: Apache HTTP server Details: USN-5090-1 fixed several vulnerabilities in Apache. This update provides the corresponding update for Ubuntu 14.04 ESM and Ubuntu 16.04 ESM. Original advisory details: It was discovered that the Apache HTTP Server incorrectly handled certain malformed requests. A remote attacker could possibly use this issue to cause the server to crash, resulting in a denial of service. (CVE-2021-34798) It was discovered that the Apache HTTP Server incorrectly handled escaping quotes. If the server was configured with third-party modules, a remote attacker could use this issue to cause the server to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2021-39275) It was discovered that the Apache mod_proxy module incorrectly handled certain request uri-paths. A remote attacker could possibly use this issue to cause the server to forward requests to arbitrary origin servers. (CVE-2021-40438) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 16.04 ESM: apache2 2.4.18-2ubuntu3.17+esm2 apache2-bin 2.4.18-2ubuntu3.17+esm2 Ubuntu 14.04 ESM: apache2 2.4.7-1ubuntu4.22+esm2 apache2-bin 2.4.7-1ubuntu4.22+esm2 In general, a standard system update will make all the necessary changes. References: https://ubuntu.com/security/notices/USN-5090-2 https://ubuntu.com/security/notices/USN-5090-1 CVE-2021-34798, CVE-2021-39275, CVE-2021-40438