CVE-2021-27239: NETGEAR Multiple Routers SSDP Stack-based Buffer Overflow Remote Code Execution Vulnerability

Published Mar 29, 2021
·
Updated

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR R6400 and R6700 firmware version 1.0.4.98 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. Was ZDI-CAN-11851.

Other sources

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

73 affected components
Netgear Multiple Routers
Netgear D6220 Firmware<1.0.0.68
Netgear D6220
Netgear D6400 Firmware<1.0.0.102
Netgear D6400
Netgear D7000 Firmware<1.0.0.66
Netgear D7000=v2
Netgear D8500 Firmware<1.0.3.60
Netgear D8500
Netgear Dc112a Firmware<1.0.0.54
Netgear DC112A
Netgear Ex7000 Firmware<1.0.1.94
Netgear EX7000
Netgear Ex7500 Firmware<1.0.0.72
Netgear EX7500
Netgear R6250 Firmware<1.0.4.48
Netgear R6250
Netgear R6300 Firmware<1.0.4.50
Netgear R6300=v2
Netgear R6400 Firmware<1.0.1.68
Netgear R6400
Netgear R6400 Firmware<1.0.4.102
Netgear R6400=v2
Netgear R6700 firmware<1.0.4.102
Netgear R6700=v3
Netgear R6900p Firmware<1.3.2.132
Netgear R6900P
Netgear R7000 Firmware<1.0.11.116
Netgear R7000
Netgear R7000p Firmware<1.3.2.132
Netgear R7000P
Netgear R7100lg Firmware<1.0.0.64
Netgear R7100LG
Netgear R7850 Firmware<1.0.5.68
Netgear R7850
Netgear R7900 Firmware<1.0.4.38
Netgear R7900
Netgear R7900p Firmware<1.4.1.68
Netgear R7900P
Netgear R7960p Firmware<1.4.1.68
Netgear R7960P
Netgear R8000 Firmware<1.0.4.68
Netgear R8000
Netgear R8000p Firmware<1.4.1.68
Netgear R8000P
Netgear R8300 Firmware<1.0.2.144
Netgear R8300
Netgear R8500 Firmware<1.0.2.144
Netgear R8500
Netgear Rax200 Firmware<1.0.2.88
Netgear RAX200
Netgear Rax75 Firmware<1.0.3.102
Netgear RAX75
Netgear Rax80 Firmware<1.0.3.102
Netgear RAX80
Netgear RBR750 firmware<3.2.17.12
Netgear RBR750
Netgear Rbr850 Firmware<3.2.17.12
Netgear RBR850
Netgear Rbs40v Firmware<2.6.2.4
Netgear RBS40V
Netgear Rbs750 Firmware<3.2.17.12
Netgear RBS750
Netgear Rbs850 Firmware<3.2.17.12
Netgear RBS850
Netgear Rs400 Firmware<=1.5.0.68
Netgear RS400
Netgear Wndr3400 Firmware<1.0.1.38
Netgear WNDR3400=v3
Netgear Wnr3500l Firmware<1.2.0.66
Netgear WNR3500L=v2
Netgear Xr300 Firmware<1.0.3.56
Netgear XR300

Event History

Mar 29, 2021
CVE Published
via MITRE·09:05 PM
Data Sourced
via MITRE·09:05 PM
DescriptionSeverityWeakness
Feb 23, 2025
Advisory Published
via ZDI·03:35 PM
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Frequently Asked Questions

1

What is the severity of CVE-2021-27239?

CVE-2021-27239 has been rated as high severity because it allows unauthenticated remote code execution on vulnerable NETGEAR routers.

2

How do I fix CVE-2021-27239?

To address CVE-2021-27239, users should update their affected NETGEAR router firmware to the latest version provided by NETGEAR.

3

Which NETGEAR devices are affected by CVE-2021-27239?

CVE-2021-27239 affects multiple NETGEAR router models including R6400 and R6700 with specific firmware versions.

4

Is authentication required to exploit CVE-2021-27239?

No, authentication is not required to exploit CVE-2021-27239, making it particularly dangerous.

5

What type of attack can occur due to CVE-2021-27239?

CVE-2021-27239 allows network-adjacent attackers to execute arbitrary code, leading potentially to a complete compromise of the affected devices.

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