5.5

CVE-2023-34327: x86/AMD: Debug Mask handling

Modified
AliasesALPINE-CVE-2023-34327UBUNTU-CVE-2023-34327DEBIAN-CVE-2023-34327
Published 05-01-2024Last modified 04-11-2025

Vulnerability summary

CVE-2023-34327 is a medium (CVSS 5.5) vulnerability in xen. EPSS estimates a 0.24% chance of exploitation in the next 30 days, higher than 15.8% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 5.5, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
5.5/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.24%
0%100%
Low · -0.01 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 9 · Related 9
OPENSUSE-SU-2024:13442-1SUSE-SU-2023:4054-1SUSE-SU-2023:4055-1SUSE-SU-2023:4174-1SUSE-SU-2023:4183-1SUSE-SU-2023:4184-1

Timeline

  1. 05-01-2024
    PublishedVulnerability first disclosed.
  2. 04-11-2025
    Last modifiedVulnerability information updated.

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.

CVSS metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

0.24%

Chance of exploitation in the next 30 days

Percentile

16%

Versus all other CVEs

30-day change

Decrease -0.01 pp

From 0.26% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Version check

Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Alpine1 product
  • xen≥ 4.5.0, < 4.15.5-r3 | ≥ 4.5.0, < 4.16.5-r3 | ≥ 4.5.0, < 4.17.2-r3
Debian1 product
  • xen< 4.17.2+76-ge1f9cb16e2-1~deb12u1 | < 4.17.2+55-g0b56bed864-1
Ubuntu1 product
  • xenAll versions (No fix recorded)
Xen1 product
  • xen≥ 4.5.0 (No fix recorded)

4 vendors · 4 products

References

7 links