CVE-2019-19338

 

Published at: - 13-07-2020 07:15

Last modified: - 26-10-2022 01:44

Total changes: - 3

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.

Common Vulnerability Scoring System (CVSS)

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

 

Verification logic

 

Reference

• https://www.openwall.com/lists/oss-security/2019/12/10/3
• https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-19338
• https://software.intel.com/security-software-guidance/insights/deep-dive-intel-transactional-synchronization-extensions-intel-tsx-asynchronous-abort

 

Keywords

NVD

 

CVE-2019-19338

 

CVE

 

Common vulnerabilities & exposures

 

CVSS

 

Common vulnerability scoring system

 

Security

 

Vulnerabilities

 

Exposures