Security Vulnerability: Register File Data Sampling (RFDS) aka CVE-2023-28746

This document (000021404) is provided subject to the disclaimer at the end of this document.

Environment

For a comprehensive list of affected products please review the SUSE Security announcement .

Situation

Security researchers have identified yet another CPU transient execution information leak, allowing information extracted from various register filesets, like floating point registers, vector registers and integer registers.

This vulnerability only affects Intel Atom processors (aka XEON E cores).

Resolution

Please install the update that contains the respective fix for this issue.
To retrieve the specific patch name, please use:

zypper lp -a --cve=CVE-2023-28746

and then use

zypper in -t patch <name_of_patch>

to apply the patch.

Status

Security Alert

Additional Information

The following options influence the mitigation:

- reg_file_data_sampling=on

If the CPU is vulnerable and fixed microcode is available, enables the mitigation.

- reg_file_data_sampling=off

Disables the mitigation.

This flag is also set by the generic "mitigations" option.

Reporting

A new reporting file was added:

/sys/devices/system/cpu/vulnerabilities/reg_file_data_sampling

This file can have following contents:

- Not affected

The CPU is not affected by the problem.

- Vulnerable

The CPU is vulnerable, but no mitigation is enabled.

- Vulnerable: No microcode

The CPU is vulnerable, but the CPU microcode is not updated.

- Mitigation: Clear Register File

The CPU is vulnerable and the CPU buffer clearing mitigation is enabled.

SUSE Security announcement:https://www.suse.com/security/cve/CVE-2023-28746

Disclaimer

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