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Vulnerability record · public intelligence
CVE-2021-20317
UNKNOWN

CVE-2021-20317

Published Sep 27, 2021 · Updated Nov 3, 2026

Severity · CVSSUNKNOWN · Not scored
Known exploitationNot listed
EPSS / likelihood0.38%
QFinch risk scoreNot available

Original summary

Normalized public record · Updated Nov 3, 2026

A flaw was found in the Linux kernel. A corrupted timer tree caused the task wakeup to be missing in the timerqueue_add function in lib/timerqueue.c. This flaw allows a local attacker with special user privileges to cause a denial of service, slowing and eventually stopping the system while running OSP.

Publisher and source text is retained separately from QFinch interpretation.

QFinch assessment

A flaw was found in the Linux kernel. A corrupted timer tree caused the task wakeup to be missing in the timerqueue_add function in lib/timerqueue.c. This flaw allows a local attacker with special user privileges to cause a denial of service, slowing and eventually stopping the system while running OSP.

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. bugzilla.redhat.com ↗
  3. [debian-lts-announce] 20211216 [SECURITY] [DLA 2843-1] linux security update ↗
  4. [debian-lts-announce] 20220309 [SECURITY] [DLA 2941-1] linux-4.19 security update ↗
  5. DSA-5096 ↗
  6. cert-portal.siemens.com ↗

Record history

Published Sep 27, 2021 · Last refreshed Nov 3, 2026

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