Virtuozzo 7 : readykernel-patch (VZA-2019-042)

medium Nessus Plugin ID 133453

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VPR Score: 6.7

Synopsis

The remote Virtuozzo host is missing a security update.

Description

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.

Solution

Update the readykernel patch.

Plugin Details

Severity: Medium

ID: 133453

File Name: Virtuozzo_VZA-2019-042.nasl

Version: 1.3

Type: local

Family: Virtuozzo Local Security Checks

Published: 2/4/2020

Updated: 1/4/2021

Dependencies: 12634

Risk Information

Risk Factor: Medium

VPR Score: 6.7

CVSS v2.0

Base Score: 6.8

Temporal Score: 5.3

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

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

Vulnerability Information

CPE: p-cpe:/a:virtuozzo:virtuozzo:readykernel, cpe:/o:virtuozzo:virtuozzo:7

Required KB Items: Host/local_checks_enabled, Host/Virtuozzo/release, Host/Virtuozzo/rpm-list, Host/readykernel-info

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 5/30/2019

Reference Information

CVE: CVE-2019-6974, CVE-2019-7221