Virtuozzo 6 : parallels-server-bm-release / vzkernel / etc (VZA-2019-052)

high Nessus Plugin ID 126175
New! Plugin Severity Now Using CVSS v3

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Synopsis

The remote Virtuozzo host is missing multiple security updates.

Description

According to the versions of the parallels-server-bm-release / vzkernel / etc packages installed, the Virtuozzo installation on the remote host is affected by the following vulnerabilities :

- A double-free can happen in idr_remove_all() in lib/idr.c in the Linux kernel. An unprivileged local attacker can use this flaw for a privilege escalation or for a system crash and a denial of service (DoS).

- An integer overflow flaw was found in the way the Linux kernel's networking subsystem processed TCP Selective Acknowledgment (SACK) segments. While processing SACK segments, the Linux kernel's socket buffer (SKB) data structure becomes fragmented. Each fragment is about TCP maximum segment size (MSS) bytes. To efficiently process SACK blocks, the Linux kernel merges multiple fragmented SKBs into one, potentially overflowing the variable holding the number of segments. A remote attacker could use this flaw to crash the Linux kernel by sending a crafted sequence of SACK segments on a TCP connection with small value of TCP MSS, resulting in a denial of service (DoS).

- tcp: excessive resource consumption while processing SACK blocks allows remote denial of service.

- tcp: excessive resource consumption for TCP connections with low MSS allows remote 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 affected parallels-server-bm-release / vzkernel / etc packages.

See Also

https://virtuozzosupport.force.com/s/article/VZA-2019-052

https://access.redhat.com/errata/RHSA-2019:1488

https://access.redhat.com/security/vulnerabilities/tcpsack

Plugin Details

Severity: High

ID: 126175

File Name: Virtuozzo_VZA-2019-052.nasl

Version: 1.3

Type: local

Published: 6/24/2019

Updated: 1/4/2021

Dependencies: ssh_get_info.nasl

Risk Information

CVSS Score Source: CVE-2019-3896

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 5.3

Vector: AV:L/AC:L/Au:N/C:C/I:C/A:C

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.8

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

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

Vulnerability Information

CPE: p-cpe:/a:virtuozzo:virtuozzo:parallels-server-bm-release, p-cpe:/a:virtuozzo:virtuozzo:vzkernel, p-cpe:/a:virtuozzo:virtuozzo:vzkernel-devel, p-cpe:/a:virtuozzo:virtuozzo:vzkernel-firmware, p-cpe:/a:virtuozzo:virtuozzo:vzmodules, p-cpe:/a:virtuozzo:virtuozzo:vzmodules-devel, cpe:/o:virtuozzo:virtuozzo:6

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

Exploit Ease: No known exploits are available

Patch Publication Date: 6/20/2019

Reference Information

CVE: CVE-2019-11477, CVE-2019-11478, CVE-2019-11479, CVE-2019-3896