Updated kernel-tmb packages fixes security vulnerabilitiesPublication date: 16 May 2019
Affected Mageia releases : 6
CVE: CVE-2018-1128 , CVE-2018-1129 , CVE-2018-12126 , CVE-2018-12127 , CVE-2018-12130 , CVE-2018-14625 , CVE-2018-16862 , CVE-2018-16882 , CVE-2018-16884 , CVE-2018-18397 , CVE-2018-19824 , CVE-2018-19985 , CVE-2018-1000026 , CVE-2019-3701 , CVE-2019-3819 , CVE-2019-3882 , CVE-2019-7308 , CVE-2019-6974 , CVE-2019-7221 , CVE-2019-7222 , CVE-2019-9213 , CVE-2019-11091 , CVE-2019-11486 , CVE-2019-11599
This kernel update provides the upstream 4.14.119 that adds the kernel side mitigations for the Microarchitectural Data Sampling (MDS, also called ZombieLoad attack) vulnerabilities in Intel processors that can allow attackers to retrieve data being processed inside a CPU. To complete the mitigations new microcode is also needed, either by installing the microcode-0.20190514-1.mga6 package, or get an updated bios / uefi firmware from the motherboard vendor. The fixed / mitigated issues are: Modern Intel microprocessors implement hardware-level micro-optimizations to improve the performance of writing data back to CPU caches. The write operation is split into STA (STore Address) and STD (STore Data) sub-operations. These sub-operations allow the processor to hand-off address generation logic into these sub-operations for optimized writes. Both of these sub-operations write to a shared distributed processor structure called the 'processor store buffer'. As a result, an unprivileged attacker could use this flaw to read private data resident within the CPU's processor store buffer. (CVE-2018-12126) Microprocessors use a ‘load port’ subcomponent to perform load operations from memory or IO. During a load operation, the load port receives data from the memory or IO subsystem and then provides the data to the CPU registers and operations in the CPU’s pipelines. Stale load operations results are stored in the 'load port' table until overwritten by newer operations. Certain load-port operations triggered by an attacker can be used to reveal data about previous stale requests leaking data back to the attacker via a timing side-channel. (CVE-2018-12127) A flaw was found in the implementation of the "fill buffer", a mechanism used by modern CPUs when a cache-miss is made on L1 CPU cache. If an attacker can generate a load operation that would create a page fault, the execution will continue speculatively with incorrect data from the fill buffer while the data is fetched from higher level caches. This response time can be measured to infer data in the fill buffer. (CVE-2018-12130) Uncacheable memory on some microprocessors utilizing speculative execution may allow an authenticated user to potentially enable information disclosure via a side channel with local access. (CVE-2019-11091) It also fixes atleast the following security issues: Cross-hyperthread Spectre v2 mitigation is now provided by the Single Thread Indirect Branch Predictors (STIBP) support. Note that STIBP also requires the functionality be supported by the Intel microcode in use. It was found that cephx authentication protocol did not verify ceph clients correctly and was vulnerable to replay attack. Any attacker having access to ceph cluster network who is able to sniff packets on network can use this vulnerability to authenticate with ceph service and perform actions allowed by ceph service (CVE-2018-1128). A flaw was found in the way signature calculation was handled by cephx authentication protocol. An attacker having access to ceph cluster network who is able to alter the message payload was able to bypass signature checks done by cephx protocol (CVE-2018-1129). A flaw was found in the Linux Kernel where an attacker may be able to have an uncontrolled read to kernel-memory from within a vm guest. A race condition between connect() and close() function may allow an attacker using the AF_VSOCK protocol to gather a 4 byte information leak or possibly intercept or corrupt AF_VSOCK messages destined to other clients (CVE-2018-14625). A security flaw was found in the Linux kernel in a way that the cleancache subsystem clears an inode after the final file truncation (removal). The new file created with the same inode may contain leftover pages from cleancache and the old file data instead of the new one (CVE-2018-16862). A use-after-free issue was found in the way the Linux kernel's KVM hypervisor processed posted interrupts when nested(=1) virtualization is enabled. In nested_get_vmcs12_pages(), in case of an error while processing posted interrupt address, it unmaps the 'pi_desc_page' without resetting 'pi_desc' descriptor address, which is later used in pi_test_and_clear_on(). A guest user/process could use this flaw to crash the host kernel resulting in DoS or potentially gain privileged access to a system (CVE-2018-16882). A flaw was found in the Linux kernel's NFS41+ subsystem. NFS41+ shares mounted in different network namespaces at the same time can make bc_svc_process() use wrong back-channel IDs and cause a use-after-free vulnerability. Thus a malicious container user can cause a host kernel memory corruption and a system panic. Due to the nature of the flaw, privilege escalation cannot be fully ruled out (CVE-2018-16884). The userfaultfd implementation in the Linux kernel before 4.19.7 mishandles access control for certain UFFDIO_ ioctl calls, as demonstrated by allowing local users to write data into holes in a tmpfs file (if the user has read-only access to that file, and that file contains holes) (CVE-2018-18397). In the Linux kernel through 4.19.6, a local user could exploit a use-after-free in the ALSA driver by supplying a malicious USB Sound device (with zero interfaces) (CVE-2018-19824). A flaw was found in the Linux kernel in the function hso_probe() which reads if_num value from the USB device (as an u8) and uses it without a length check to index an array, resulting in an OOB memory read in hso_probe() or hso_get_config_data(). An attacker with a forged USB device and physical access to a system (needed to connect such a device) can cause a system crash and a denial of service (CVE-2018-19985). Linux Linux kernel version at least v4.8 onwards, probably well before contains a Insufficient input validation vulnerability in bnx2x network card driver that can result in DoS: Network card firmware assertion takes card off-line. This attack appear to be exploitable via An attacker on a must pass a very large, specially crafted packet to the bnx2x card. This can be done from an untrusted guest VM (CVE-2018-1000026) An issue was discovered in can_can_gw_rcv in net/can/gw.c in the Linux kernel through 4.19.13. The CAN frame modification rules allow bitwise logical operations that can be also applied to the can_dlc field. Because of a missing check, the CAN drivers may write arbitrary content beyond the data registers in the CAN controller's I/O memory when processing can-gw manipulated outgoing frames. This is related to cgw_csum_xor_rel. An unprivileged user can trigger a system crash (general protection fault) (CVE-2019-3701). A flaw was found in the Linux kernel in the function hid_debug_events_read() in drivers/hid/hid-debug.c file which may enter an infinite loop with certain parameters passed from a userspace. A local privileged user ("root") can cause a system lock up and a denial of service (CVE-2019-3819). A flaw was found in the Linux kernel's vfio interface implementation that permits violation of the user's locked memory limit. If a device is bound to a vfio driver, such as vfio-pci, and the local attacker is administratively granted ownership of the device, it may cause a system memory exhaustion and thus a denial of service (DoS) (CVE-2019-3882). In the Linux kernel before 4.20.8, kvm_ioctl_create_device in virt/kvm/kvm_main.c mishandles reference counting because of a race condition, leading to a use-after-free (CVE-2019-6974). A use-after-free vulnerability was found in the way the Linux kernel's KVM hypervisor emulates a preemption timer for L2 guests when nested (=1) virtualization is enabled. This high resolution timer(hrtimer) runs when a L2 guest is active. After VM exit, the sync_vmcs12() timer object is stopped. The use-after-free occurs if the timer object is freed before calling sync_vmcs12() routine. A guest user/process could use this flaw to crash the host kernel resulting in a denial of service or, potentially, gain privileged access to a system (CVE-2019-7221). An information leakage issue was found in the way Linux kernel's KVM hypervisor handled page fault exceptions while emulating instructions like VMXON, VMCLEAR, VMPTRLD, and VMWRITE with memory address as an operand. It occurs if the operand is a mmio address, as the returned exception object holds uninitialized stack memory contents. A guest user/process could use this flaw to leak host's stack memory contents to a guest (CVE-2019-7222). kernel/bpf/verifier.c in the Linux kernel before 4.20.6 performs undesirable out-of-bounds speculation on pointer arithmetic in various cases, including cases of different branches with different state or limits to sanitize, leading to side-channel attacks (CVE-2019-7308). In the Linux kernel before 4.20.14, expand_downwards in mm/mmap.c lacks a check for the mmap minimum address, which makes it easier for attackers to exploit kernel NULL pointer dereferences on non-SMAP platforms. This is related to a capability check for the wrong task (CVE-2019-9213). The Siemens R3964 line discipline driver in drivers/tty/n_r3964.c in the Linux kernel before 5.0.8 has multiple race conditions (CVE-2019-11486). The coredump implementation in the Linux kernel before 5.0.10 does not use locking or other mechanisms to prevent vma layout or vma flags changes while it runs, which allows local users to obtain sensitive information, cause a denial of service, or possibly have unspecified other impact by triggering a race condition with mmget_not_zero or get_task_mm calls (CVE-2019-11599). It also fixes signal handling issues causing powertop to crash and some tracing tools to fail on execve tests. Ndiswrapper has been updated to 1.62 WireGuard has been updated to 0.0.20190406. For other uptstream fixes in this update, see the referenced changelogs.