Cyber Resilience

CVE-2023-34322

Xen 3.2.0 – 4.15.0

Published
05 January 2024
Modified
04 November 2025
Patch / advisory
CVSS Score v3.1 7.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0023 14th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2023-34322 is a high-severity Improper Check for Dropped Privileges (CWE-273) vulnerability in Xen Xen. Its CVSS base score is 7.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Access Token Manipulation (T1134); ranked at the 14th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-6 (Least Privilege) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

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…

more

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.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1134 Access Token Manipulation Stealth
Adversaries may modify access tokens to operate under a different user or system security context to perform actions and bypass access controls.
T1548 Abuse Elevation Control Mechanism Privilege Escalation
Adversaries may circumvent mechanisms designed to control privilege elevation to gain higher-level permissions.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-58143Same product: Xen Xen
CVE-2026-23554Same product: Xen Xen
CVE-2024-45818Same product: Xen Xen
CVE-2026-23553Same product: Xen Xen
CVE-2023-46837Same product: Xen Xen
CVE-2024-45819Same product: Xen Xen
CVE-2023-34323Same product: Xen Xen
CVE-2025-58144Same product: Xen Xen
CVE-2024-31143Same product: Xen Xen
CVE-2025-58149Same product: Xen Xen

Affected Assets

xen
xen
3.2.0 — 4.15.0

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

Employing least privilege requires that privilege-dropping operations succeed and are verified before continuing.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC activities (code review, static analysis, testing) catch missing or incorrect privilege-drop checks, but eliminating only this one flaw covers only a fraction of the control's broader intent.

PR.AA-05 partial match
prevents

Least-privilege policy and enforcement directly motivate privilege-dropping code, yet the control does not address implementation-level verification of the drop.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing can detect failed privilege drops, yet the control does not require such checks as part of its core intent.

degrades

Control of privileged utility programs includes ensuring privilege-dropping operations are verified before use.

degrades

Privileged access rights policy requires verification that privilege changes succeed, directly addressing failed privilege drops.

prevents

Secure coding practices can prevent missing privilege-drop checks, but the control itself does not mandate verification of privilege changes.

References