high
8.8
CWE
787 121
Advisory Published
Updated
Advisory Published

CVE-2021-34991: NETGEAR R6400v2 UPnP uuid Stack-based Buffer Overflow Remote Code Execution Vulnerability

First published: Mon Nov 15 2021(Updated: )

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR R6400v2 1.0.4.106_10.0.80 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the UPnP service, which listens on TCP port 5000 by default. When parsing the uuid request header, the process does not properly validate 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-14110.

Credit: zdi-disclosures@trendmicro.com

Affected SoftwareAffected VersionHow to fix
NETGEAR R6400v2 firmware
Netgear EX3700<1.0.0.94
Netgear EX3700
NETGEAR EX3800 firmware<1.0.0.94
NETGEAR EX3800 firmware
NETGEAR EX6120 firmware<1.0.0.66
Netgear EX6120
NETGEAR EX6130<1.0.0.66
NETGEAR EX6130
NETGEAR R6400 firmware<1.0.1.76
NETGEAR R6400 firmware
NETGEAR R6400v2 firmware<1.0.4.120
NETGEAR R6400v2 firmware
Netgear R6700 Firmware<1.0.4.120
NETGEAR R6700v3 firmware
NETGEAR R6900P firmware<1.3.3.142
Netgear R6900 Firmware
Netgear Nighthawk R7000 Firmware<1.0.11.128
NETGEAR Nighthawk R7000
NETGEAR R7000P firmware<1.3.3.142
Netgear Routers
NETGEAR R7100LG firmware<1.0.0.72
Netgear R7100LG
NETGEAR R7850<1.0.5.76
NETGEAR R7850 firmware
NETGEAR R7900P firmware<1.4.2.84
NETGEAR R7900P firmware
NETGEAR R7960P firmware<1.4.2.84
NETGEAR R7960P firmware
NETGEAR R8000 firmware<1.0.4.76
NETGEAR R8000 firmware
NETGEAR R8000P<1.4.2.84
NETGEAR R8000P firmware
NETGEAR R8300 firmware<1.0.2.156
NETGEAR R8300 firmware
NETGEAR R8500<1.0.2.156
NETGEAR R8500
NETGEAR RAX15 firmware<1.0.4.100
NETGEAR RAX15 firmware
NETGEAR RAX20 firmware<1.0.4.100
NETGEAR RAX20 firmware
NETGEAR RAX200 firmware<1.0.5.132
NETGEAR RAX200 firmware
NETGEAR RAX35v2 firmware<1.0.4.100
NETGEAR RAX35v2 firmware
NETGEAR RAX38v2 Firmware<1.0.4.100
NETGEAR RAX38v2 Firmware
NETGEAR RAX40v2 firmware<1.0.4.100
NETGEAR RAX40v2 firmware
NETGEAR RAX42<1.0.4.100
NETGEAR RAX42 Firmware
Netgear RAX43<1.0.4.100
Netgear RAX43
NETGEAR RAX45 firmware<1.0.4.100
NETGEAR RAX45 firmware
NETGEAR RAX48<1.0.4.100
NETGEAR RAX48 Firmware
NETGEAR RAX50<1.0.4.100
NETGEAR RAX50
NETGEAR RAX50<1.0.4.100
NETGEAR RAX50
NETGEAR RAX75 firmware<1.0.5.132
NETGEAR RAX75 firmware
NETGEAR RAX80 Firmware<1.0.5.132
NETGEAR RAX80 firmware
NETGEAR RAXE450 Firmware<1.0.8.70
NETGEAR raxe450 firmware
NETGEAR RAXE500 Firmware<1.0.8.70
NETGEAR RAXE500 Firmware
NETGEAR RS400 firmware<1.5.1.80
NETGEAR RS400 firmware
NETGEAR WNDR3400v3 firmware<1.0.1.42
NETGEAR WNDR3400v3 firmware
NETGEAR WNR3500Lv2<1.2.0.70
NETGEAR WNR3500Lv2 firmware
Netgear NMS300 Firmware<1.0.3.68
Netgear NMS300 Firmware
Netgear D6220 Firmware<1.0.0.76
NETGEAR D6220 firmware
NETGEAR D6400<1.0.0.108
NETGEAR D6400 firmware
NETGEAR D7000 firmware<1.0.0.76
NETGEAR D7000v2 firmware
NETGEAR DGN2200Bv4 firmware<1.0.0.126
NETGEAR DGN2200Bv4
NETGEAR DC112A firmware<1.0.0.62
Netgear DC112A
NETGEAR CAX80<2.1.3.5
NETGEAR CAX80 Firmware

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-34991?

    CVE-2021-34991 has been rated as critical due to its potential to allow arbitrary code execution without authentication.

  • How do I fix CVE-2021-34991?

    To fix CVE-2021-34991, update the firmware of the affected NETGEAR R6400v2 routers to version 1.0.4.120 or later.

  • Which devices are affected by CVE-2021-34991?

    CVE-2021-34991 affects NETGEAR R6400v2 routers running firmware version 1.0.4.106_10.0.80.

  • Can CVE-2021-34991 be exploited remotely?

    Yes, CVE-2021-34991 can be exploited remotely by network-adjacent attackers without requiring authentication.

  • Is my NETGEAR R6400v2 router vulnerable to CVE-2021-34991?

    If your NETGEAR R6400v2 router is running firmware version 1.0.4.106_10.0.80 or older, it is vulnerable to CVE-2021-34991.

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