CVE-2021-3512: High severity Buffalo BHR-4GRV firmware vulnerability

Published Apr 28, 2021
·
Updated

Improper access control vulnerability in Buffalo broadband routers (BHR-4GRV firmware Ver.1.99 and prior, DWR-HP-G300NH firmware Ver.1.83 and prior, HW-450HP-ZWE firmware Ver.1.99 and prior, WHR-300HP firmware Ver.1.99 and prior, WHR-300 firmware Ver.1.99 and prior, WHR-G301N firmware Ver.1.86 and prior, WHR-HP-G300N firmware Ver.1.99 and prior, WHR-HP-GN firmware Ver.1.86 and prior, WPL-05G300 firmware Ver.1.87 and prior, WZR-450HP-CWT firmware Ver.1.99 and prior, WZR-450HP-UB firmware Ver.1.99 and prior, WZR-HP-AG300H firmware Ver.1.75 and prior, WZR-HP-G300NH firmware Ver.1.83 and prior, WZR-HP-G301NH firmware Ver.1.83 and prior, WZR-HP-G302H firmware Ver.1.85 and prior, WZR-HP-G450H firmware Ver.1.89 and prior, WZR-300HP firmware Ver.1.99 and prior, WZR-450HP firmware Ver.1.99 and prior, WZR-600DHP firmware Ver.1.99 and prior, WZR-D1100H firmware Ver.1.99 and prior, FS-HP-G300N firmware Ver.3.32 and prior, FS-600DHP firmware Ver.3.38 and prior, FS-R600DHP firmware Ver.3.39 and prior, and FS-G300N firmware Ver.3.13 and prior) allows remote unauthenticated attackers to bypass access restriction and to start telnet service and execute arbitrary OS commands with root privileges via unspecified vectors.

Affected Software

96 affected components
Buffalo BHR-4GRV firmware<2.00
Buffalo BHR-4GRV
Buffalo DWR-HP-G300NH firmware<1.84
Buffalo DWR-HP-G300NH
Buffalo HW-450HP-ZWE firmware<2.00
Buffalo HW-450HP-ZWE
Buffalo WHR-300HP firmware<2.00
Buffalo WHR-300HP
Buffalo WHR-300 firmware<2.00
Buffalo WHR-300
Buffalo WHR-G301N firmware<1.87
Buffalo WHR-G301N
Buffalo WHR-HP-G300N firmware<2.00
Buffalo WHR-HP-G300N
Buffalo WHR-HP-GN firmware<1.87
Buffalo WHR-HP-GN
Buffalo WPL-05G300 firmware<1.88
Buffalo WPL-05G300
Buffalo WZR-450HP-CWT firmware<2.00
Buffalo WZR-450HP-CWT
Buffalo WZR-450HP-UB firmware<2.00
Buffalo WZR-450HP-UB
Buffalo WZR-HP-AG300H firmware<1.76
Buffalo WZR-HP-AG300H
Buffalo WZR-HP-G300NH firmware<1.84
Buffalo WZR-HP-G300NH
Buffalo WZR-HP-G301NH firmware<1.84
Buffalo WZR-HP-G301NH
Buffalo WZR-HP-G302H firmware<1.86
Buffalo WZR-HP-G302H
Buffalo WZR-HP-G450H firmware<1.90
Buffalo WZR-HP-G450H
Buffalo WZR-300HP firmware<2.00
Buffalo WZR-300HP
Buffalo WZR-450HP firmware<2.00
Buffalo WZR-450HP
Buffalo WZR-600DHP firmware<2.00
Buffalo WZR-600DHP
Buffalo WZR-D1100H firmware<2.00
Buffalo WZR-D1100H
Buffalo FS-HP-G300N firmware<3.33
Buffalo FS-HP-G300N
Buffalo FS-600DHP firmware<3.40
Buffalo FS-600DHP
Buffalo FS-R600DHP firmware<3.40
Buffalo FS-R600DHP
Buffalo FS-G300N firmware<3.14
Buffalo FS-G300N
All of the following
Buffalo BHR-4GRV firmware<2.00
Buffalo BHR-4GRV
All of the following
Buffalo DWR-HP-G300NH firmware<1.84
Buffalo DWR-HP-G300NH
All of the following
Buffalo HW-450HP-ZWE firmware<2.00
Buffalo HW-450HP-ZWE
All of the following
Buffalo WHR-300HP firmware<2.00
Buffalo WHR-300HP
All of the following
Buffalo WHR-300 firmware<2.00
Buffalo WHR-300
All of the following
Buffalo WHR-G301N firmware<1.87
Buffalo WHR-G301N
All of the following
Buffalo WHR-HP-G300N firmware<2.00
Buffalo WHR-HP-G300N
All of the following
Buffalo WHR-HP-GN firmware<1.87
Buffalo WHR-HP-GN
All of the following
Buffalo WPL-05G300 firmware<1.88
Buffalo WPL-05G300
All of the following
Buffalo WZR-450HP-CWT firmware<2.00
Buffalo WZR-450HP-CWT
All of the following
Buffalo WZR-450HP-UB firmware<2.00
Buffalo WZR-450HP-UB
All of the following
Buffalo WZR-HP-AG300H firmware<1.76
Buffalo WZR-HP-AG300H
All of the following
Buffalo WZR-HP-G300NH firmware<1.84
Buffalo WZR-HP-G300NH
All of the following
Buffalo WZR-HP-G301NH firmware<1.84
Buffalo WZR-HP-G301NH
All of the following
Buffalo WZR-HP-G302H firmware<1.86
Buffalo WZR-HP-G302H
All of the following
Buffalo WZR-HP-G450H firmware<1.90
Buffalo WZR-HP-G450H
All of the following
Buffalo WZR-300HP firmware<2.00
Buffalo WZR-300HP
All of the following
Buffalo WZR-450HP firmware<2.00
Buffalo WZR-450HP
All of the following
Buffalo WZR-600DHP firmware<2.00
Buffalo WZR-600DHP
All of the following
Buffalo WZR-D1100H firmware<2.00
Buffalo WZR-D1100H
All of the following
Buffalo FS-HP-G300N firmware<3.33
Buffalo FS-HP-G300N
All of the following
Buffalo FS-600DHP firmware<3.40
Buffalo FS-600DHP
All of the following
Buffalo FS-R600DHP firmware<3.40
Buffalo FS-R600DHP
All of the following
Buffalo FS-G300N firmware<3.14
Buffalo FS-G300N

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Compensating control

    Apply network-level containment for affected Buffalo broadband routers by restricting inbound access to prevent remote unauthenticated attackers from reaching the services affected by the improper access control vulnerability (including preventing external access to the telnet service).

Event History

Apr 28, 2021
CVE Published
via MITRE·12:45 AM
Data Sourced
via MITRE·12:45 AM
DescriptionWeakness
Data Sourced
via NVD·01:15 AM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the vulnerability ID?

The vulnerability ID is CVE-2021-3512.

2

What is the severity of CVE-2021-3512?

The severity of CVE-2021-3512 is high with a severity value of 8.8.

3

Which Buffalo broadband routers are affected by CVE-2021-3512?

Buffalo broadband routers including BHR-4GRV firmware Ver.1.99 and prior, DWR-HP-G300NH firmware Ver.1.83 and prior, HW-450HP-ZWE firmware Ver.1.99 and prior, WHR-300HP firmware Ver.1.99 and prior, WHR-300 firmware Ver.1.99 and prior, and WHR-G301N firmware Ver.1.86 and prior are affected by CVE-2021-3512.

4

What is the description of CVE-2021-3512?

CVE-2021-3512 is an improper access control vulnerability in Buffalo broadband routers.

5

Are Buffalo BHR-4GRV routers vulnerable to CVE-2021-3512?

Yes, Buffalo BHR-4GRV routers with firmware Ver.1.99 and prior are vulnerable to CVE-2021-3512.

Contact

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