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Vulnerability record · public intelligence
CVE-2022-42332
UNKNOWN

CVE-2022-42332

Published Mar 21, 2023 · Updated Nov 3, 2026

Severity · CVSSUNKNOWN · Not scored
Known exploitationNot listed
EPSS / likelihood0.27%
QFinch risk scoreNot available

Original summary

Normalized public record · Updated Nov 3, 2026

x86 shadow plus log-dirty mode use-after-free In environments where host assisted address translation is necessary but Hardware Assisted Paging (HAP) is unavailable, Xen will run guests in so called shadow mode. Shadow mode maintains a pool of memory used for both shadow page tables as well as auxiliary data structures. To migrate or snapshot guests, Xen additionally runs them in so called log-dirty mode. The data structures needed by the log-dirty tracking are part of aformentioned auxiliary data. In order to keep error handling efforts within reasonable bounds, for operations which may requi

Publisher and source text is retained separately from QFinch interpretation.

QFinch assessment

x86 shadow plus log-dirty mode use-after-free In environments where host assisted address translation is necessary but Hardware Assisted Paging (HAP) is unavailable, Xen will run guests in so called shadow mode. Shadow mode maintains a pool of memory used for both shadow page tables as well as auxiliary data structures. To migrate or snapshot guests, Xen additionally runs them in so called log-dirty mode. The data structures needed by the log-dirty tracking are part of aformentioned auxiliary data. In order to keep error handling efforts within reasonable bounds, for operations which may require memory allocations shadow mode logic ensures up front that enough memory is available for the worst case requirements. Unfortunately, while page table memory is properly accounted for on the code path requiring the potential establishing of new shadows, demands by the log-dirty infrastructure were not taken into consideration. As a result, just established shadow page tables could be freed again immediately, while other code is still accessing them on the assumption that they would remain allocated.

Evidence: public source records

Affected products

Affected scope reported by the available public evidence
Affected package, product or rangeFix status
Consult the referenced vendor advisory for affected versions.Consult source advisory

Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.

Remediation

Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.

  1. Confirm the affected product and reachable code path exist in your environment.
  2. Apply the vendor-supported patch or mitigation from the primary advisory.
  3. Rescan the exact deployed revision and retain verification evidence.
Review primary references

Evidence coverage

FIRST-EPSSCVE-LIST-V5
SSVC priority
MEDIUM
Confidence
Not available
Aliases
None reported

Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.

Sources and record history

  1. xenbits.xenproject.org ↗
  2. xenbits.xen.org ↗
  3. [oss-security] 20230321 Xen Security Advisory 427 v2 (CVE-2022-42332) - x86 shadow plus log-dirty mode use-after-free ↗
  4. FEDORA-2023-703f133eb3 ↗
  5. FEDORA-2023-da8315e641 ↗
  6. DSA-5378 ↗
  7. security.gentoo.org ↗

Record history

Published Mar 21, 2023 · Last refreshed Nov 3, 2026

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