The 4.20.8 stable kernel update contains a number of important fixes across the tree.

Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website.
Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

Security Fix(es) :

  - Kernel: KVM: potential use-after-free via     kvm_ioctl_create_device() (CVE-2019-6974)

  - Kernel: KVM: nVMX: use-after-free of the hrtimer for     emulation of the preemption timer (CVE-2019-7221)

Bug Fix(es) :

  - rbd: avoid corruption on partially completed bios     [rhel-7.6.z]

  - xfs_vm_writepages deadly embrace between kworker and     user task. [rhel-7.6.z]

  - Offload Connections always get vlan priority 0     [rhel-7.6.z]

  - [NOKIA] SL sends flood of Neighbour Solicitations under     specific conditions [rhel-7.6.z]

  - SL 7.6 - Host crash occurred on NVMe/IB system while     running controller reset [rhel-7.6.z]

  - [rhel7] raid0 md workqueue deadlock with stacked md     devices [rhel-7.6.z]

  - [PureStorage7.6]nvme disconnect following an     unsuccessful Admin queue creation causes kernel panic     [rhel-7.6.z]

  - RFC: Regression with -fstack-check in 'backport upstream     large stack guard patch to SL6' patch [rhel-7.6.z]

  - [Hyper-V] [SL 7.6]hv_netvsc: Fix a network regression     after ifdown/ifup [rhel-7.6.z]

  - rtc_cmos: probe of 00:01 failed with error -16     [rhel-7.6.z]

  - ACPI WDAT watchdog update [rhel-7.6.z]

  - high ovs-vswitchd CPU usage when VRRP over VXLAN tunnel     causing qrouter fail-over [rhel-7.6.z]

  - Openshift node drops outgoing POD traffic due to NAT     hashtable race in __ip_conntrack_confirm() [rhel-7.6.z]

  - [Backport] [v3,2/2] net: igmp: Allow user-space     configuration of igmp unsolicited report interval     [rhel-7.6.z]

  - [SL7.6]: Intermittently seen FIFO parity error on     T6225-SO adapter [rhel-7.6.z]

  - The number of unsolict report about IGMP is incorrect     [rhel-7.6.z]

  - RDT driver causing failure to boot on AMD Rome system     with more than 255 CPUs [rhel-7.6.z]

  - mpt3sas_cm0: fault_state(0x2100)! [rhel-7.6.z]

  - rwsem in inconsistent state leading system to hung     [rhel-7.6.z]

According to the version of the vzkernel package and the readykernel-patch installed, the Virtuozzo installation on the remote host is affected by the following vulnerabilities :

  - A use-after-free vulnerability was found in the way KVM     implements its device control API. When a device is     created via kvm_ioctl_create_device(), it holds a     reference to a VM object. This reference is transferred     to file descriptor table of the caller. If such file     descriptor was closed, reference count to the VM object     could become zero, which could lead to a use-after-free     issue. A user/process could use this flaw to crash the     guest VM resulting in a denial of service or,     potentially, gain privileged access to a system.

  - A use-after-free vulnerability was found in the way KVM     emulates a preemption timer for L2 guests when nested     virtualization is enabled. 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.

  - It was discovered that a certain sequence of operations     related to IPv4 routing could trigger a kernel memory     leak. An attacker could potentially exploit that from a     container to cause a denial of service.

Note that Tenable Network Security has extracted the preceding description block directly from the Virtuozzo security advisory.
Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - 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)

Note that Nessus relies on the presence of the package as reported by the vendor.

The remote Ubuntu 14.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-3932-2 advisory.

    USN-3932-1 fixed vulnerabilities in the Linux kernel for Ubuntu 16.04 LTS. This update provides the     corresponding updates for the Linux Hardware Enablement (HWE) kernel from Ubuntu 16.04 LTS for Ubuntu     14.04 LTS.

    It was discovered that a race condition existed in the f2fs file system implementation in the Linux     kernel. A local attacker could use this to cause a denial of service. (CVE-2017-18249)

    Wen Xu discovered that the f2fs file system 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-2018-13097, CVE-2018-13099, CVE-2018-13100, CVE-2018-14614,     CVE-2018-14616)

    Wen Xu and Po-Ning Tseng discovered that btrfs file system implementation in the Linux kernel did not     properly validate metadata. An attacker could use this to construct a malicious btrfs image that, when     mounted, could cause a denial of service (system crash). (CVE-2018-14610, CVE-2018-14611, CVE-2018-14612,     CVE-2018-14613)

    Vasily Averin and Evgenii Shatokhin discovered that a use-after-free vulnerability existed in the NFS41+     subsystem when multiple network namespaces are in use. A local attacker in a container could use this to     cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2018-16884)

    It was discovered that a use-after-free vulnerability existed in the PPP over L2TP implementation in the     Linux kernel. A privileged local attacker could use this to possibly execute arbitrary code.
    (CVE-2018-9517)

    Shlomi Oberman, Yuli Shapiro, and Ran Menscher discovered an information leak in the Bluetooth     implementation of the Linux kernel. An attacker within Bluetooth range could use this to expose sensitive     information (kernel memory). (CVE-2019-3459, CVE-2019-3460)

    Jann Horn discovered that the KVM implementation in the Linux kernel contained a use-after-free     vulnerability. An attacker in a guest VM with access to /dev/kvm could use this to cause a denial of     service (guest VM crash). (CVE-2019-6974)

    Jim Mattson and Felix Wilhelm discovered a use-after-free vulnerability in the KVM subsystem of the Linux     kernel, when using nested virtual machines. A local attacker in a guest VM could use this to cause a     denial of service (system crash) or possibly execute arbitrary code in the host system. (CVE-2019-7221)

    Felix Wilhelm discovered that an information leak vulnerability existed in the KVM subsystem of the Linux     kernel, when nested virtualization is used. A local attacker could use this to expose sensitive     information (host system memory to a guest VM). (CVE-2019-7222)

    Jann Horn discovered that the mmap implementation in the Linux kernel did not properly check for the mmap     minimum address in some situations. A local attacker could use this to assist exploiting a kernel NULL     pointer dereference vulnerability. (CVE-2019-9213)

    Muyu Yu discovered that the CAN implementation in the Linux kernel in some situations did not properly     restrict the field size when processing outgoing frames. A local attacker with CAP_NET_ADMIN privileges     could use this to execute arbitrary code. (CVE-2019-3701)

    Vladis Dronov discovered that the debug interface for the Linux kernel's HID subsystem did not properly     validate passed parameters in some situations. A local privileged attacker could use this to cause a     denial of service (infinite loop). (CVE-2019-3819)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	名称	产品	系列	发布时间	最近更新时间	严重程度
122275	Fedora 29 : kernel / kernel-headers / kernel-tools (2019-164946aa7f)	Nessus	Fedora Local Security Checks	2019/2/19	2024/6/20	high
122278	Fedora 28 : kernel / kernel-headers / kernel-tools (2019-3da64f3e61)	Nessus	Fedora Local Security Checks	2019/2/19	2024/6/20	high
124290	Scientific Linux Security Update : kernel on SL7.x x86_64 (20190423)	Nessus	Scientific Linux Local Security Checks	2019/4/25	2024/5/31	high
133453	Virtuozzo 7 : readykernel-patch (VZA-2019-042)	Nessus	Virtuozzo Local Security Checks	2020/2/4	2024/3/28	high
133454	Virtuozzo 7 : readykernel-patch (VZA-2019-045)	Nessus	Virtuozzo Local Security Checks	2020/2/4	2024/3/28	high
245487	Linux Distros Unpatched Vulnerability : CVE-2019-6974	Nessus	Misc.	2025/8/7	2025/8/7	high
123681	Ubuntu 14.04 LTS : Linux kernel (Xenial HWE) vulnerabilities (USN-3932-2)	Nessus	Ubuntu Local Security Checks	2019/4/3	2024/8/27	high

检测

插件搜索

high

high

high

high

high

high

high