ZDI-21-206: NETGEAR Multiple Routers SSDP Stack-based Buffer Overflow Remote Code Execution Vulnerability

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR R6400 and R6700 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the upnpd service, which listens on UDP port 1900 by default. A crafted MX header field in an SSDP message can trigger an overflow of 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
Netgear Multiple Routers

Event History

Feb 23, 2025
Advisory Published
via ZDI·03:35 PM
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Frequently Asked Questions

1

What is the severity of ZDI-21-206?

The severity of ZDI-21-206 is critical due to the potential for arbitrary code execution without authentication.

2

How do I fix ZDI-21-206?

To fix ZDI-21-206, users should update their NETGEAR R6400 and R6700 routers to the latest firmware provided by NETGEAR.

3

Who is affected by ZDI-21-206?

ZDI-21-206 affects users of NETGEAR R6400 and R6700 routers that have the vulnerable upnpd service enabled.

4

Can ZDI-21-206 be exploited remotely?

Yes, ZDI-21-206 can be exploited remotely by network-adjacent attackers without the need for authentication.

5

What are the potential consequences of ZDI-21-206?

The potential consequences of ZDI-21-206 include unauthorized access to the router, data breaches, and full system compromise.

Contact

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