Virtuozzo 7 : readykernel-patch (VZA-2019-050)

High Nessus Plugin ID 133456

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 :

- An integer overflow 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.

- An excessive resource consumption issue 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, which leads to increased resource utilization to traverse and process these fragments as further SACK segments are received on the same TCP connection. A remote attacker could use this flaw to cause a denial of service (DoS) by sending a crafted sequence of SACK segments on a TCP connection.

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.

See Also

https://virtuozzosupport.force.com/s/article/VZA-2019-050

https://readykernel.com/patch/1572/

https://readykernel.com/patch/1574/

https://readykernel.com/patch/1576/

https://readykernel.com/patch/1578/

https://readykernel.com/patch/1579/

https://readykernel.com/patch/1582/

https://readykernel.com/patch/1583/

https://readykernel.com/patch/1584/

https://readykernel.com/patch/1587/

https://readykernel.com/patch/1590/

Plugin Details

Severity: High

ID: 133456

File Name: Virtuozzo_VZA-2019-050.nasl

Version: 1.2

Type: local

Published: 2020/02/04

Updated: 2020/02/07

Dependencies: 12634

Risk Information

Risk Factor: High

CVSS v2.0

Base Score: 7.8

Temporal Score: 5.8

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

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

CVSS v3.0

Base Score: 7.5

Temporal Score: 6.5

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

Temporal Vector: CVSS:3.0/E:U/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 Ease: No known exploits are available

Patch Publication Date: 2019/06/20

Reference Information

CVE: CVE-2019-11477, CVE-2019-11478