CVE-2019-19338

Published Jul 13, 2020

Last updated 4 years ago

Overview

Description
A flaw was found in the fix for CVE-2019-11135, in the Linux upstream kernel versions before 5.5 where, the way Intel CPUs handle speculative execution of instructions when a TSX Asynchronous Abort (TAA) error occurs. When a guest is running on a host CPU affected by the TAA flaw (TAA_NO=0), but is not affected by the MDS issue (MDS_NO=1), the guest was to clear the affected buffers by using a VERW instruction mechanism. But when the MDS_NO=1 bit was exported to the guests, the guests did not use the VERW mechanism to clear the affected buffers. This issue affects guests running on Cascade Lake CPUs and requires that host has 'TSX' enabled. Confidentiality of data is the highest threat associated with this vulnerability.
Source
secalert@redhat.com
NVD status
Analyzed

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Severity
MEDIUM

CVSS 3.0

Type
Secondary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Severity
MEDIUM

CVSS 2.0

Type
Primary
Base score
2.1
Impact score
2.9
Exploitability score
3.9
Vector string
AV:L/AC:L/Au:N/C:P/I:N/A:N

Weaknesses

nvd@nist.gov
CWE-203
secalert@redhat.com
CWE-203

Social media

Hype score
Not currently trending

Configurations