CVE-2020-27866: NETGEAR Multiple Routers mini_httpd Authentication Bypass Vulnerability

Published Feb 11, 2021
·
Updated

This vulnerability allows network-adjacent attackers to bypass authentication on affected installations of NETGEAR R6020, R6080, R6120, R6220, R6260, R6700v2, R6800, R6900v2, R7450, JNR3210, WNR2020, Nighthawk AC2100, and Nighthawk AC2400 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the minihttpd service, which listens on TCP port 80 by default. The issue results from incorrect string matching logic when accessing protected pages. An attacker can leverage this in conjunction with other vulnerabilities to execute code in the context of root.

Affected Software

39 affected components
Netgear Multiple Routers
Netgear Ac2100 Firmware<1.2.0.76
Netgear AC2100
Netgear Ac2400 Firmware<1.2.0.76
Netgear AC2400
Netgear Ac2600 Firmware<1.2.0.76
Netgear AC2600
Netgear R6700 firmware<1.2.0.76
Netgear R6700=v2
Netgear R6800 Firmware<1.2.0.76
Netgear R6800
Netgear R6900 Firmware<1.2.0.76
Netgear R6900=v2
Netgear R7200 Firmware<1.2.0.76
Netgear R7200
Netgear R7350 Firmware<1.2.0.76
Netgear R7350
Netgear R7400 Firmware<1.2.0.76
Netgear R7400
Netgear R7450 Firmware<1.2.0.76
Netgear R7450
Netgear R6220 Firmware<1.1.0.104
Netgear R6220
Netgear R6230 Firmware<1.1.0.104
Netgear R6230
Netgear R6260 Firmware<1.1.0.78
Netgear R6260
Netgear R6330 Firmware<1.1.0.78
Netgear R6330
Netgear R6350 Firmware<1.1.0.78
Netgear R6350
Netgear R6850 Firmware<1.1.0.78
Netgear R6850
Netgear R6120 Firmware<1.0.0.76
Netgear R6120
Netgear R6020 Firmware<1.0.0.48
Netgear R6020
Netgear R6080 Firmware<1.0.0.48
Netgear R6080

Event History

Feb 11, 2021
CVE Published
via MITRE·11:35 PM
Data Sourced
via MITRE·11:35 PM
DescriptionSeverityWeakness
Feb 23, 2025
Advisory Published
via ZDI·03:35 PM
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Frequently Asked Questions

1

What is the vulnerability ID for this NETGEAR router authentication bypass?

The vulnerability ID for this NETGEAR router authentication bypass is CVE-2020-27866.

2

Which routers are affected by the NETGEAR router authentication bypass vulnerability?

The affected routers include NETGEAR R6020, R6080, R6120, R6220, R6260, R6700v2, R6800, R6900v2, R7450, JNR3210, WNR2020, Nighthawk AC2100, and Nighthawk AC2400.

3

How severe is the NETGEAR router authentication bypass vulnerability?

The severity of the NETGEAR router authentication bypass vulnerability is rated as high with a severity value of 8.8.

4

How can network-adjacent attackers exploit the NETGEAR router authentication bypass vulnerability?

Network-adjacent attackers can exploit the vulnerability by bypassing authentication on the affected installations.

5

What is the recommended action to fix the NETGEAR router authentication bypass vulnerability?

NETGEAR has released a security advisory with recommended steps to mitigate the vulnerability. Please refer to their official knowledge base article for more information.

Contact

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