TSX Transaction Asynchronous Abort (TAA)
CVE: CVE-2019-11135
Component: hw
CWE: CWE-385
Severity: Moderate
CVSS v3: 6.3/CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
Release date: 2019-11-12T18:00:00+00:00

A flaw was found in the way Intel CPUs handle speculative execution of instructions when the TSX Asynchronous Abort (TAA) error occurs. A local authenticated attacker with the ability to monitor execution times could infer the TSX memory state by comparing abort execution times. This could allow information disclosure via this observed side-channel for any TSX transaction being executed while an attacker is able to observe abort timing.

Intel's Transactional Synchronisation Extensions (TSX) are set of instructions which enable transactional memory support to improve performance of the multi-threaded applications, in the lock-protected critical sections. The CPU executes instructions in the critical-sections as transactions, while ensuring their atomic state. When such transaction execution is unsuccessful, the processor cannot ensure atomic updates to the transaction memory, so the processor rolls back or aborts such transaction execution.

While TSX Asynchronous Abort (TAA) is pending, CPU may continue to read data from architectural buffers and pass it to the dependent speculative operations. This may cause information leakage via speculative side-channel means, which is quite similar to the Microarchitectural Data Sampling (MDS) issue.

Statement: libvirt and qemu-kvm on Red Hat Enterprise Linux 6 are not affected by this vulnerability as they do not support MSR-based CPU features.

Remediation:
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

After installing this update, shut down all running virtual machines. Once all virtual machines have shut down, start them again for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

After installing this update, shut down all running virtual machines. Once all virtual machines have shut down, start them again for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/2974891
Before applying this update, make sure all previously released errata relevant to your system have been applied.

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258
Before applying this update, make sure all previously released errata relevant to your system have been applied.

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/2974891

After installing this update, shut down all running virtual machines. Once all virtual machines have shut down, start them again for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
Before applying this update, make sure all previously released errata relevant to your system have been applied.

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258
For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

The system must be rebooted for this update to take effect.
For mitigation related information, please refer to the Red Hat Knowledgebase article:  https://access.redhat.com/solutions/tsx-asynchronousabort