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Vulnerability record · public intelligence
CVE-2020-36311
UNKNOWN

CVE-2020-36311

Published Apr 6, 2021 · Updated Nov 3, 2026

Severity · CVSSUNKNOWN · Not scored
Known exploitationNot listed
EPSS / likelihood0.34%
QFinch risk scoreNot available

Original summary

Normalized public record · Updated Nov 3, 2026

An issue was discovered in the Linux kernel before 5.9. arch/x86/kvm/svm/sev.c allows attackers to cause a denial of service (soft lockup) by triggering destruction of a large SEV VM (which requires unregistering many encrypted regions), aka CID-7be74942f184.

Publisher and source text is retained separately from QFinch interpretation.

QFinch assessment

An issue was discovered in the Linux kernel before 5.9. arch/x86/kvm/svm/sev.c allows attackers to cause a denial of service (soft lockup) by triggering destruction of a large SEV VM (which requires unregistering many encrypted regions), aka CID-7be74942f184.

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
LOW
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. Patch commit ↗
  2. cdn.kernel.org ↗
  3. [debian-lts-announce] 20210720 [SECURITY] [DLA 2714-1] linux-4.19 security update ↗
  4. DSA-4941 ↗

Record history

Published Apr 6, 2021 · Last refreshed Nov 3, 2026

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