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CVE-2022-33745
UNKNOWN

CVE-2022-33745

Published Jul 26, 2022 · Updated Nov 3, 2026

Severity · CVSSUNKNOWN · Not scored
Known exploitationNot listed
EPSS / likelihood0.30%
QFinch risk scoreNot available

Original summary

Normalized public record · Updated Nov 3, 2026

insufficient TLB flush for x86 PV guests in shadow mode For migration as well as to work around kernels unaware of L1TF (see XSA-273), PV guests may be run in shadow paging mode. To address XSA-401, code was moved inside a function in Xen. This code movement missed a variable changing meaning / value between old and new code positions. The now wrong use of the variable did lead to a wrong TLB flush condition, omitting flushes where such are necessary.

Publisher and source text is retained separately from QFinch interpretation.

QFinch assessment

insufficient TLB flush for x86 PV guests in shadow mode For migration as well as to work around kernels unaware of L1TF (see XSA-273), PV guests may be run in shadow paging mode. To address XSA-401, code was moved inside a function in Xen. This code movement missed a variable changing meaning / value between old and new code positions. The now wrong use of the variable did lead to a wrong TLB flush condition, omitting flushes where such are necessary.

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] 20220726 Xen Security Advisory 408 v2 (CVE-2022-33745) - insufficient TLB flush for x86 PV guests in shadow mode ↗
  4. [oss-security] 20220726 Xen Security Advisory 408 v3 (CVE-2022-33745) - insufficient TLB flush for x86 PV guests in shadow mode ↗
  5. FEDORA-2022-4f7cd241e2 ↗
  6. FEDORA-2022-a0d7a5eaf2 ↗
  7. DSA-5272 ↗

Record history

Published Jul 26, 2022 · Last refreshed Nov 3, 2026

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