CVE-2023-34322

top-level shadow reference dropped too early for 64-bit PV guests

State
Published
Severity
7.8 High
Published
Jan 5, 2024
Updated
Nov 4, 2025
Reserved
Jun 1, 2023

Read the record on cve.org

Description

For migration as well as to work around kernels unaware of L1TF (see XSA-273), PV guests may be run in shadow paging mode. Since Xen itself needs to be mapped when PV guests run, Xen and shadowed PV guests run directly the respective shadow page tables. For 64-bit PV guests this means running on the shadow of the guest root page table.

In the course of dealing with shortage of memory in the shadow pool associated with a domain, shadows of page tables may be torn down. This tearing down may include the shadow root page table that the CPU in question is presently running on. While a precaution exists to supposedly prevent the tearing down of the underlying live page table, the time window covered by that precaution isn't large enough.

Scores

CVSSScoreVectorSource
3.17.8 HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HCISA-ADP

Weaknesses

  • CWE-273 Improper Check for Dropped Privileges

Affected Products

ProductVersions
XenXen
  • consult Xen advisory XSA-438Unknown

References

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.