CVE-2021-3511

Severity: medium (CVSS 4.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-04-28 · updated 2026-06-17

Description

Disclosure of sensitive information to an unauthorized user 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 obtain information such as configuration via unspecified vectors.

Affected products

Buffalo Bhr-4Grv Firmware: before 2.00 — fixed in 2.00
Buffalo Dwr-Hp-G300Nh Firmware: before 1.84 — fixed in 1.84
Buffalo Fs-600Dhp Firmware: before 3.40 — fixed in 3.40
Buffalo Fs-G300N Firmware: before 3.14 — fixed in 3.14
Buffalo Fs-Hp-G300N Firmware: before 3.33 — fixed in 3.33
Buffalo Fs-R600Dhp Firmware: before 3.40 — fixed in 3.40
Buffalo Hw-450Hp-Zwe Firmware: before 2.00 — fixed in 2.00
Buffalo Whr-300 Firmware: before 2.00 — fixed in 2.00
Buffalo Whr-300Hp Firmware: before 2.00 — fixed in 2.00
Buffalo Whr-G301N Firmware: before 1.87 — fixed in 1.87
Buffalo Whr-Hp-G300N Firmware: before 2.00 — fixed in 2.00
Buffalo Whr-Hp-Gn Firmware: before 1.87 — fixed in 1.87
Buffalo Wpl-05G300 Firmware: before 1.88 — fixed in 1.88
Buffalo Wzr-300Hp Firmware: before 2.00 — fixed in 2.00
Buffalo Wzr-450Hp-Cwt Firmware: before 2.00 — fixed in 2.00
Buffalo Wzr-450Hp-Ub Firmware: before 2.00 — fixed in 2.00
Buffalo Wzr-450Hp Firmware: before 2.00 — fixed in 2.00
Buffalo Wzr-600Dhp Firmware: before 2.00 — fixed in 2.00
Buffalo Wzr-D1100H Firmware: before 2.00 — fixed in 2.00
Buffalo Wzr-Hp-Ag300H Firmware: before 1.76 — fixed in 1.76
Buffalo Wzr-Hp-G300Nh Firmware: before 1.84 — fixed in 1.84
Buffalo Wzr-Hp-G301Nh Firmware: before 1.84 — fixed in 1.84
Buffalo Wzr-Hp-G302H Firmware: before 1.86 — fixed in 1.86
Buffalo Wzr-Hp-G450H Firmware: before 1.90 — fixed in 1.90

How to fix

Upgrade to a fixed version: Buffalo Bhr-4Grv Firmware 2.00; Buffalo Dwr-Hp-G300Nh Firmware 1.84; Buffalo Fs-600Dhp Firmware 3.40; Buffalo Fs-G300N Firmware 3.14; Buffalo Fs-Hp-G300N Firmware 3.33; Buffalo Fs-R600Dhp Firmware 3.40; Buffalo Hw-450Hp-Zwe Firmware 2.00; Buffalo Whr-300 Firmware 2.00; Buffalo Whr-300Hp Firmware 2.00; Buffalo Whr-G301N Firmware 1.87; Buffalo Whr-Hp-G300N Firmware 2.00; Buffalo Whr-Hp-Gn Firmware 1.87. Check the vendor advisory for mitigations.

References

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