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CVE-2021-40847

HIGH CVSS: 8.1 Published: 2021-09-21 Modified: 2026-06-17

Description

The update process of the Circle Parental Control Service on various NETGEAR routers allows remote attackers to achieve remote code execution as root via a MitM attack. While the parental controls themselves are not enabled by default on the routers, the Circle update daemon, circled, is enabled by default. This daemon connects to Circle and NETGEAR to obtain version information and updates to the circled daemon and its filtering database. However, database updates from NETGEAR are unsigned and downloaded via cleartext HTTP. As such, an attacker with the ability to perform a MitM attack on the device can respond to circled update requests with a crafted, compressed database file, the extraction of which gives the attacker the ability to overwrite executable files with attacker-controlled code. This affects R6400v2 1.0.4.106, R6700 1.0.2.16, R6700v3 1.0.4.106, R6900 1.0.2.16, R6900P 1.3.2.134, R7000 1.0.11.123, R7000P 1.3.2.134, R7850 1.0.5.68, R7900 1.0.4.38, R8000 1.0.4.68, and RS400 1.5.0.68.

Affected Platforms

Netgear R6400V2Netgear R8000 FirmwareNetgear R6900PNetgear R6900 FirmwareNetgear Rs400 FirmwareNetgear R6700V3 FirmwareNetgear R7850 FirmwareNetgear R6900P FirmwareNetgear R7000 FirmwareNetgear R7900

Weakness Type

CWE-319

References