ZDI-21-977: D-Link DAP-2020 webproc 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 webproc endpoint, which listens on TCP port 80 by default. 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-21-977?

ZDI-21-977 has a high severity rating due to the ability for network-adjacent attackers to execute arbitrary code without authentication.

2

How do I fix ZDI-21-977?

To fix ZDI-21-977, update the D-Link DAP-2020 router firmware to the latest version provided by D-Link.

3

Who is affected by ZDI-21-977?

The vulnerability ZDI-21-977 affects installations of D-Link DAP-2020 routers that have not been updated to the patched firmware.

4

What type of attacks can be performed using ZDI-21-977?

ZDI-21-977 can be exploited to execute arbitrary code on the vulnerable D-Link DAP-2020 routers, potentially leading to full system compromise.

5

Is authentication required to exploit ZDI-21-977?

No, authentication is not required to exploit the ZDI-21-977 vulnerability, making it particularly dangerous.

Contact

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ZDI-21-977 - D-Link DAP-2020 webproc Stack-based Buffer Overflow Remote Code Execution Vulnerability - SecAlerts