========================================================================== Ubuntu Security Notice USN-6537-1 December 06, 2023 linux-gcp vulnerabilities ========================================================================== A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 23.10 Summary: Several security issues were fixed in the Linux kernel. Software Description: - linux-gcp: Linux kernel for Google Cloud Platform (GCP) systems Details: Yu Hao discovered that the UBI driver in the Linux kernel did not properly check for MTD with zero erasesize during device attachment. A local privileged attacker could use this to cause a denial of service (system crash). (CVE-2023-31085) Lucas Leong discovered that the netfilter subsystem in the Linux kernel did not properly validate some attributes passed from userspace. A local attacker could use this to cause a denial of service (system crash) or possibly expose sensitive information (kernel memory). (CVE-2023-39189) Bien Pham discovered that the netfiler subsystem in the Linux kernel contained a race condition, leading to a use-after-free vulnerability. A local user could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2023-4244) Kyle Zeng discovered that the IPv4 implementation in the Linux kernel did not properly handle socket buffers (skb) when performing IP routing in certain circumstances, leading to a null pointer dereference vulnerability. A privileged attacker could use this to cause a denial of service (system crash). (CVE-2023-42754) Yikebaer Aizezi discovered that the ext4 file system implementation in the Linux kernel contained a use-after-free vulnerability when handling inode extent metadata. An attacker could use this to construct a malicious ext4 file system image that, when mounted, could cause a denial of service (system crash). (CVE-2023-45898) Maxim Levitsky discovered that the KVM nested virtualization (SVM) implementation for AMD processors in the Linux kernel did not properly handle x2AVIC MSRs. An attacker in a guest VM could use this to cause a denial of service (host kernel crash). (CVE-2023-5090) Jason Wang discovered that the virtio ring implementation in the Linux kernel did not properly handle iov buffers in some situations. A local attacker in a guest VM could use this to cause a denial of service (host system crash). (CVE-2023-5158) Alon Zahavi discovered that the NVMe-oF/TCP subsystem in the Linux kernel did not properly handle queue initialization failures in certain situations, leading to a use-after-free vulnerability. A remote attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2023-5178) It was discovered that the SMB network file sharing protocol implementation in the Linux kernel did not properly handle certain error conditions, leading to a use-after-free vulnerability. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2023-5345) Murray McAllister discovered that the VMware Virtual GPU DRM driver in the Linux kernel did not properly handle memory objects when storing surfaces, leading to a use-after-free vulnerability. A local attacker in a guest VM could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2023-5633) Budimir Markovic discovered that the perf subsystem in the Linux kernel did not properly handle event groups, leading to an out-of-bounds write vulnerability. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2023-5717) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 23.10: linux-image-6.5.0-1010-gcp 6.5.0-1010.10 linux-image-gcp 6.5.0.1010.10 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://ubuntu.com/security/notices/USN-6537-1 CVE-2023-31085, CVE-2023-39189, CVE-2023-4244, CVE-2023-42754, CVE-2023-45898, CVE-2023-5090, CVE-2023-5158, CVE-2023-5178, CVE-2023-5345, CVE-2023-5633, CVE-2023-5717 Package Information: https://launchpad.net/ubuntu/+source/linux-gcp/6.5.0-1010.10