CVE-2021-27255: NETGEAR BR200 Firmware

High severity, CVSS 8.8. EPSS: 1.4% chance of exploitation in the next 30 days.

This vulnerability allows remote attackers to execute arbitrary code on affected installations of NETGEAR R7800 firmware version 1.0.2.76. Authentication is not required to exploit this vulnerability. The specific flaw exists within the refresh_status.aspx endpoint. The issue results from a lack of authentication required to start a service on the server. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-12360.

Affected products

NETGEAR BR200 Firmware: before 5.10.0.5 (fixed in 5.10.0.5)
NETGEAR BR500 Firmware: before 5.10.0.5 (fixed in 5.10.0.5)
NETGEAR d7800 Firmware: before 1.0.1.60 (fixed in 1.0.1.60)
NETGEAR EX6100V2 Firmware: before 1.0.1.98 (fixed in 1.0.1.98)
NETGEAR EX6150V2 Firmware: before 1.0.1.98 (fixed in 1.0.1.98)
NETGEAR EX6250 Firmware: before 1.0.0.134 (fixed in 1.0.0.134)
NETGEAR EX6400 Firmware: before 1.0.2.158 (fixed in 1.0.2.158)
NETGEAR EX6400V2 Firmware: before 1.0.0.134 (fixed in 1.0.0.134)
NETGEAR EX6410 Firmware: before 1.0.0.134 (fixed in 1.0.0.134)
NETGEAR EX6420 Firmware: before 1.0.0.134 (fixed in 1.0.0.134)
NETGEAR EX7300 Firmware: before 1.0.2.158 (fixed in 1.0.2.158)
NETGEAR EX7300V2 Firmware: before 1.0.0.134 (fixed in 1.0.0.134)
NETGEAR EX7320 Firmware: before 1.0.0.134 (fixed in 1.0.0.134)
NETGEAR EX7700 Firmware: before 1.0.0.216 (fixed in 1.0.0.216)
NETGEAR EX8000 Firmware: before 1.0.1.232 (fixed in 1.0.1.232)
NETGEAR LBR20 Firmware: before 2.6.3.50 (fixed in 2.6.3.50)
NETGEAR r7800 Firmware: before 1.0.2.80 (fixed in 1.0.2.80)
NETGEAR r8900 Firmware: before 1.0.5.28 (fixed in 1.0.5.28)
NETGEAR r9000 Firmware: before 1.0.5.28 (fixed in 1.0.5.28)
NETGEAR RBK12 Firmware: before 2.7.2.104 (fixed in 2.7.2.104)
NETGEAR RBK13 Firmware: before 2.7.2.104 (fixed in 2.7.2.104)
NETGEAR RBK14 Firmware: before 2.7.2.104 (fixed in 2.7.2.104)
NETGEAR RBK15 Firmware: before 2.7.2.104 (fixed in 2.7.2.104)
NETGEAR RBK20 Firmware: before 2.6.2.104 (fixed in 2.6.2.104)
NETGEAR RBK23 Firmware: before 2.7.2.104 (fixed in 2.7.2.104)
and 18 more

Published 2021-03-05. Last modified 2026-06-17.