========================================================================== Ubuntu Security Notice USN-4981-1 June 03, 2021 squid, squid3 vulnerabilities ========================================================================== A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 21.04 - Ubuntu 20.10 - Ubuntu 20.04 LTS - Ubuntu 18.04 LTS Summary: Several security issues were fixed in Squid. Software Description: - squid: Web proxy cache server - squid3: Web proxy cache server Details: Joshua Rogers discovered that Squid incorrectly handled requests with the urn: scheme. A remote attacker could possibly use this issue to cause Squid to consume resources, leading to a denial of service. (CVE-2021-28651) Joshua Rogers discovered that Squid incorrectly handled requests to the Cache Manager API. A remote attacker with access privileges could possibly use this issue to cause Squid to consume resources, leading to a denial of service. This issue was only addressed in Ubuntu 20.04 LTS, Ubuntu 20.10, and Ubuntu 21.04. (CVE-2021-28652) Joshua Rogers discovered that Squid incorrectly handled certain response headers. A remote attacker could possibly use this issue to cause Squid to crash, resulting in a denial of service. This issue was only affected Ubuntu 20.04 LTS, Ubuntu 20.10, and Ubuntu 21.04. (CVE-2021-28662) Joshua Rogers discovered that Squid incorrectly handled range request processing. A remote attacker could possibly use this issue to cause Squid to crash, resulting in a denial of service. (CVE-2021-31806, CVE-2021-31807, CVE-2021-31808) Joshua Rogers discovered that Squid incorrectly handled certain HTTP responses. A remote attacker could possibly use this issue to cause Squid to crash, resulting in a denial of service. (CVE-2021-33620) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 21.04: squid 4.13-1ubuntu4.1 Ubuntu 20.10: squid 4.13-1ubuntu2.2 Ubuntu 20.04 LTS: squid 4.10-1ubuntu1.4 Ubuntu 18.04 LTS: squid 3.5.27-1ubuntu1.11 In general, a standard system update will make all the necessary changes. References: https://ubuntu.com/security/notices/USN-4981-1 CVE-2021-28651, CVE-2021-28652, CVE-2021-28662, CVE-2021-31806, CVE-2021-31807, CVE-2021-31808, CVE-2021-33620 Package Information: https://launchpad.net/ubuntu/+source/squid/4.13-1ubuntu4.1 https://launchpad.net/ubuntu/+source/squid/4.13-1ubuntu2.2 https://launchpad.net/ubuntu/+source/squid/4.10-1ubuntu1.4 https://launchpad.net/ubuntu/+source/squid3/3.5.27-1ubuntu1.11