NewStart CGSL CORE 5.05 / MAIN 5.05 : kernel-rt Multiple Vulnerabilities (NS-SA-2019-0086)

Medium Nessus Plugin ID 127302

Synopsis

The remote machine is affected by multiple vulnerabilities.

Description

The remote NewStart CGSL host, running version CORE 5.05 / MAIN 5.05, has kernel-rt packages installed that are affected by multiple vulnerabilities:

- 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 CPUs 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)

- A use-after-free vulnerability was found in the way the Linux kernel's KVM hypervisor implements its device control API. While creating a device via kvm_ioctl_create_device(), the device holds a reference to a VM object, later this reference is transferred to the caller's file descriptor table. If such file descriptor was to be closed, reference count to the VM object could become zero, potentially leading to a use- after-free issue. A user/process could use this flaw to crash the guest VM resulting in a denial of service issue or, potentially, gain privileged access to a system. (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)

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

Solution

Upgrade the vulnerable CGSL kernel-rt packages. Note that updated packages may not be available yet. Please contact ZTE for more information.

See Also

http://security.gd-linux.com/notice/NS-SA-2019-0086

Plugin Details

Severity: Medium

ID: 127302

File Name: newstart_cgsl_NS-SA-2019-0086_kernel-rt.nasl

Version: 1.2

Type: local

Published: 2019/08/12

Updated: 2019/09/24

Dependencies: 12634

Risk Information

Risk Factor: Medium

CVSS Score Source: CVE-2019-6974

CVSS v2.0

Base Score: 6.8

Temporal Score: 5.3

Vector: CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:P

Temporal Vector: CVSS2#E:POC/RL:OF/RC:C

CVSS v3.0

Base Score: 8.1

Temporal Score: 7.3

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

Vulnerability Information

Required KB Items: Host/local_checks_enabled, Host/ZTE-CGSL/release, Host/ZTE-CGSL/rpm-list, Host/cpu

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 2019/07/17

Vulnerability Publication Date: 2019/02/15

Reference Information

CVE: CVE-2018-12126, CVE-2018-12127, CVE-2018-12130, CVE-2019-6974, CVE-2019-7221, CVE-2019-7222

BID: 107127, 107294, 106963