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Vulnerability record · public intelligence
CVE-2021-33270
UNKNOWN

CVE-2021-33270

Published Dec 1, 2021 · Updated Nov 3, 2026

Severity · CVSSUNKNOWN · Not scored
Known exploitationNot listed
EPSS / likelihood3.96%
QFinch risk scoreNot available

Original summary

Normalized public record · Updated Nov 3, 2026

D-Link DIR-809 devices with firmware through DIR-809Ax_FW1.12WWB03_20190410 were discovered to contain a stack buffer overflow vulnerability in the function FUN_800462c4 in /formAdvFirewall. This vulnerability is triggered via a crafted POST request.

Publisher and source text is retained separately from QFinch interpretation.

QFinch assessment

D-Link DIR-809 devices with firmware through DIR-809Ax_FW1.12WWB03_20190410 were discovered to contain a stack buffer overflow vulnerability in the function FUN_800462c4 in /formAdvFirewall. This vulnerability is triggered via a crafted POST request.

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. www.dlink.com ↗
  2. Source repository ↗

Record history

Published Dec 1, 2021 · Last refreshed Nov 3, 2026

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