Vulnerability in NETGEAR R6400v2
CVE-2021-40847
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.
EPSS: 0.101 (95.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Netgear R6400v2
- Netgear R6400v2_firmware — versions 1.0.4.106
- Netgear R6700
- Netgear R6700_firmware — versions 1.0.2.16
- Netgear R6700v3
- Netgear R6700v3_firmware — versions 1.0.4.106
- Netgear R6900
- Netgear R6900_firmware — versions 1.0.2.16
- Netgear R6900p
- Netgear R6900p_firmware — versions 1.3.2.134
Weakness classification (CWE)
Public proof-of-concept exploits
References
- cve@mitre.org (x_refsource_MISC, Vendor Advisory)
- cve@mitre.org (Exploit, Third Party Advisory, x_refsource_MISC)
Frequently asked questions
- What is CVE-2021-40847?
- CVE-2021-40847 is a high-severity vulnerability in NETGEAR R6400v2, classified under Cleartext Transmission of Sensitive Information. CVSS score: 8.1/10. Published 2021-09-21.
- How severe is CVE-2021-40847?
- High severity. CVSS v3 base score is 8.1 out of 10.
- Is CVE-2021-40847 known to be exploited?
- 4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.