CVE-2021-34863: D-Link DAP-2020 webproc var:page Stack-based Buffer Overflow Remote Code Execution Vulnerability

Published Oct 25, 2021
·
Updated

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:page 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-13271.

Other sources

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of D-Link DAP-2020 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of the var:page 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.

ZDI

Affected Software

3 affected components
Dlink Dap-2020 Firmware<=1.01
Dlink Dap-2020
D-Link DAP-2020

Event History

Oct 25, 2021
CVE Published
via MITRE·05:10 PM
Data Sourced
via MITRE·05:10 PM
DescriptionSeverityWeakness
Feb 28, 2025
Advisory Published
via ZDI·12:15 PM
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Frequently Asked Questions

1

What is the vulnerability ID of this D-Link DAP-2020 vulnerability?

The vulnerability ID is CVE-2021-34863.

2

What is the title of this D-Link DAP-2020 vulnerability?

The title of this vulnerability is D-Link DAP-2020 webproc var:page Stack-based Buffer Overflow Remote Code Execution Vulnerability.

3

How severe is CVE-2021-34863?

The severity of CVE-2021-34863 is high.

4

How can attackers exploit CVE-2021-34863?

Attackers can exploit CVE-2021-34863 by executing arbitrary code on affected D-Link DAP-2020 1.01rc001 routers.

5

Are authentication credentials required to exploit CVE-2021-34863?

No, authentication is not required to exploit CVE-2021-34863.

6

Which software versions are affected by CVE-2021-34863?

D-Link DAP-2020 routers running firmware version 1.01 are affected by CVE-2021-34863.

7

Is the D-Link DAP-2020 device itself vulnerable?

Yes, the D-Link DAP-2020 device is vulnerable to CVE-2021-34863.

8

What is the Common Weakness Enumeration (CWE) ID of CVE-2021-34863?

The CWE ID of CVE-2021-34863 is CWE-121.

Contact

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