CVE-2021-34862

Original summary

Normalized public record · Updated Oct 23, 2026

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of D-Link DAP-2020 1.01rc001 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of the var:menu parameter provided to the webproc endpoint. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-13270.

Publisher and source text is retained separately from QFinch interpretation.

Affected products

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.

Evidence coverage

SSVC priority

MEDIUM

Confidence

10%

Aliases

None reported

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

Sources and record history

1. supportannouncement.us.dlink.com ↗
2. www.zerodayinitiative.com ↗

Record history

Published Oct 25, 2021 · Last refreshed Oct 23, 2026