========================================================================== Ubuntu Security Notice USN-3821-1 November 14, 2018 linux, linux-aws, linux-kvm, linux-raspi2, linux-snapdragon vulnerabilities ========================================================================== A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 16.04 LTS Summary: Several security issues were fixed in the Linux kernel. Software Description: - linux: Linux kernel - linux-aws: Linux kernel for Amazon Web Services (AWS) systems - linux-kvm: Linux kernel for cloud environments - linux-raspi2: Linux kernel for Raspberry Pi 2 - linux-snapdragon: Linux kernel for Snapdragon processors Details: Wen Xu discovered that the ext4 filesystem implementation in the Linux kernel did not properly ensure that xattr information remained in inode bodies. An attacker could use this to construct a malicious ext4 image that, when mounted, could cause a denial of service (system crash). (CVE-2018-10880) It was discovered that the alarmtimer implementation in the Linux kernel contained an integer overflow vulnerability. A local attacker could use this to cause a denial of service. (CVE-2018-13053) Wen Xu discovered that the f2fs filesystem implementation in the Linux kernel did not properly validate metadata. An attacker could use this to construct a malicious f2fs image that, when mounted, could cause a denial of service (system crash). (CVE-2018-13096) Wen Xu and Po-Ning Tseng discovered that the btrfs filesystem implementation in the Linux kernel did not properly handle relocations in some situations. An attacker could use this to construct a malicious btrfs image that, when mounted, could cause a denial of service (system crash). (CVE-2018-14609) Wen Xu discovered that the HFS+ filesystem implementation in the Linux kernel did not properly handle malformed catalog data in some situations. An attacker could use this to construct a malicious HFS+ image that, when mounted, could cause a denial of service (system crash). (CVE-2018-14617) Jann Horn discovered that the procfs file system implementation in the Linux kernel did not properly restrict the ability to inspect the kernel stack of an arbitrary task. A local attacker could use this to expose sensitive information. (CVE-2018-17972) It was discovered that the KVM implementation in the Linux kernel on ARM 64bit processors did not properly handle some ioctls. An attacker with the privilege to create KVM-based virtual machines could use this to cause a denial of service (host system crash) or execute arbitrary code in the host. (CVE-2018-18021) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 16.04 LTS: linux-image-4.4.0-1037-kvm 4.4.0-1037.43 linux-image-4.4.0-1072-aws 4.4.0-1072.82 linux-image-4.4.0-1100-raspi2 4.4.0-1100.108 linux-image-4.4.0-1104-snapdragon 4.4.0-1104.109 linux-image-4.4.0-139-generic 4.4.0-139.165 linux-image-4.4.0-139-generic-lpae 4.4.0-139.165 linux-image-4.4.0-139-lowlatency 4.4.0-139.165 linux-image-4.4.0-139-powerpc-e500mc 4.4.0-139.165 linux-image-4.4.0-139-powerpc-smp 4.4.0-139.165 linux-image-4.4.0-139-powerpc64-emb 4.4.0-139.165 linux-image-4.4.0-139-powerpc64-smp 4.4.0-139.165 linux-image-aws 4.4.0.1072.74 linux-image-generic 4.4.0.139.145 linux-image-generic-lpae 4.4.0.139.145 linux-image-kvm 4.4.0.1037.36 linux-image-lowlatency 4.4.0.139.145 linux-image-powerpc-e500mc 4.4.0.139.145 linux-image-powerpc-smp 4.4.0.139.145 linux-image-powerpc64-emb 4.4.0.139.145 linux-image-powerpc64-smp 4.4.0.139.145 linux-image-raspi2 4.4.0.1100.100 linux-image-snapdragon 4.4.0.1104.96 After a standard system update you need to reboot your computer to make all the necessary changes. ATTENTION: Due to an unavoidable ABI change the kernel updates have been given a new version number, which requires you to recompile and reinstall all third party kernel modules you might have installed. Unless you manually uninstalled the standard kernel metapackages (e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual, linux-powerpc), a standard system upgrade will automatically perform this as well. References: https://usn.ubuntu.com/usn/usn-3821-1 CVE-2018-10880, CVE-2018-13053, CVE-2018-13096, CVE-2018-14609, CVE-2018-14617, CVE-2018-17972, CVE-2018-18021 Package Information: https://launchpad.net/ubuntu/+source/linux/4.4.0-139.165 https://launchpad.net/ubuntu/+source/linux-aws/4.4.0-1072.82 https://launchpad.net/ubuntu/+source/linux-kvm/4.4.0-1037.43 https://launchpad.net/ubuntu/+source/linux-raspi2/4.4.0-1100.108 https://launchpad.net/ubuntu/+source/linux-snapdragon/4.4.0-1104.109