PT-2021-20827 · Buffalo · Fs-600Dhp+22

Chuya Hayakawa · Published 2021-04-28 · Updated 2022-07-12 · CVE-2021-3512

Positive Technologies (AI Summary)

CVSS v3.1

8.8

High

Base vector

AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions: Buffalo broadband routers versions 1.99 and prior Buffalo DWR-HP-G300NH firmware versions 1.83 and prior Buffalo HW-450HP-ZWE firmware versions 1.99 and prior Buffalo WHR-300HP firmware versions 1.99 and prior Buffalo WHR-300 firmware versions 1.99 and prior Buffalo WHR-G301N firmware versions 1.86 and prior Buffalo WHR-HP-G300N firmware versions 1.99 and prior Buffalo WHR-HP-GN firmware versions 1.86 and prior Buffalo WPL-05G300 firmware versions 1.87 and prior Buffalo WZR-450HP-CWT firmware versions 1.99 and prior Buffalo WZR-450HP-UB firmware versions 1.99 and prior Buffalo WZR-HP-AG300H firmware versions 1.75 and prior Buffalo WZR-HP-G300NH firmware versions 1.83 and prior Buffalo WZR-HP-G301NH firmware versions 1.83 and prior Buffalo WZR-HP-G302H firmware versions 1.85 and prior Buffalo WZR-HP-G450H firmware versions 1.89 and prior Buffalo WZR-300HP firmware versions 1.99 and prior Buffalo WZR-450HP firmware versions 1.99 and prior Buffalo WZR-600DHP firmware versions 1.99 and prior Buffalo WZR-D1100H firmware versions 1.99 and prior Buffalo FS-HP-G300N firmware versions 3.32 and prior Buffalo FS-600DHP firmware versions 3.38 and prior Buffalo FS-R600DHP firmware versions 3.39 and prior Buffalo FS-G300N firmware versions 3.13 and prior

Description: The issue is related to improper access control in Buffalo broadband routers, allowing remote unauthenticated attackers to bypass access restrictions. This enables them to start the telnet service and execute arbitrary OS commands with root privileges via unspecified vectors.

Recommendations: For Buffalo broadband routers and all listed firmware versions, update to a version later than the specified affected version to resolve the issue. As a temporary workaround, consider disabling the telnet service on the affected devices until a patch is available. Restrict access to the affected routers to minimize the risk of exploitation.

Fix

Related Identifiers

CVE-2021-3512

Affected Products

Buffalo Broadband Routers

Dwr-Hp-G300Nh

Fs-600Dhp

Fs-G300N

Fs-Hp-G300N

Fs-R600Dhp

Hw-450Hp-Zwe

Whr-300

Whr-300Hp

Whr-G301N

Whr-Hp-G300N

Whr-Hp-Gn

Wpl-05G300

Wzr-300Hp

Wzr-450Hp

Wzr-450Hp-Cwt

Wzr-450Hp-Ub

Wzr-600Dhp

Wzr-D1100H

Wzr-Hp-Ag300H

Wzr-Hp-G301Nh

Wzr-Hp-G302H

Wzr-Hp-G450H

References · 4

• https://osv.dev/vulnerability/CVE-2021-3512 · Vendor Advisory
• https://buffalo.jp/news/detail/20210427-01.html · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2021-3512 · Security Note
• https://jvn.jp/en/vu/JVNVU99235714/index.html · Note