CVE-2021-34862

Name: CVE-2021-34862
Creator: NVD / NIST
Published: 2021-10-25T17:15:08.537+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 0.79%

Last modified Jun 17, 2026

CVE-2021-34862 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. 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. EPSS estimates a 0.79% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

8.8/10

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

0.79%

51.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-121

Affected Software

Vendor	Product	Versions
Dlink	Dap-2020 Firmware	<= 1.01

References

https://supportannouncement.us.dlink.com/announcement/publication.aspx?name=SAP10201Patch, Vendor Advisory
https://www.zerodayinitiative.com/advisories/ZDI-21-978/Third Party Advisory, VDB Entry
https://supportannouncement.us.dlink.com/announcement/publication.aspx?name=SAP10201Patch, Vendor Advisory
https://www.zerodayinitiative.com/advisories/ZDI-21-978/Third Party Advisory, VDB Entry

Timeline

Published: Oct 25, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-34862?

How severe is CVE-2021-34862?

CVE-2021-34862 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 0.79% probability of exploitation in the next 30 days.

How do I fix CVE-2021-34862?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-34862?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST