CVE-2023-34328

x86/AMD: Debug Mask handling

State
Published
Severity
5.5 Medium
Published
Jan 5, 2024
Updated
Nov 4, 2025
Reserved
Jun 1, 2023

Read the record on cve.org

Description

[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.]

AMD CPUs since ~2014 have extensions to normal x86 debugging functionality. Xen supports guests using these extensions.

Unfortunately there are errors in Xen's handling of the guest state, leading to denials of service.

1) CVE-2023-34327 - An HVM vCPU can end up operating in the context of a previous vCPUs debug mask state.

2) CVE-2023-34328 - A PV vCPU can place a breakpoint over the live GDT. This allows the PV vCPU to exploit XSA-156 / CVE-2015-8104 and lock up the CPU entirely.

Scores

CVSSScoreVectorSource
3.15.5 MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HCISA-ADP

Weaknesses

The record names no weakness.

Affected Products

ProductVersions
XenXen
  • consult Xen advisory XSA-444Unknown

References

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