ZDI-21-978: D-Link DAP-2020 webproc var:menu Stack-based Buffer Overflow Remote Code Execution Vulnerability

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: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.

Affected Software

1 affected component
D-Link DAP-2020

Event History

Feb 28, 2025
Advisory Published
via ZDI·12:15 PM
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Frequently Asked Questions

1

What is the severity of ZDI-21-978?

The ZDI-21-978 vulnerability has a high severity rating due to its potential for arbitrary code execution.

2

How do I fix ZDI-21-978?

To mitigate ZDI-21-978, users should update their D-Link DAP-2020 routers to the latest firmware version provided by D-Link.

3

Who is affected by ZDI-21-978?

The ZDI-21-978 vulnerability affects installations of D-Link DAP-2020 routers.

4

Can ZDI-21-978 be exploited remotely?

Yes, ZDI-21-978 can be exploited by network-adjacent attackers without the need for authentication.

5

What is the nature of the flaw in ZDI-21-978?

The nature of the flaw in ZDI-21-978 involves improper handling of the var:menu parameter, allowing code execution.

Contact

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