8.1
HIGH
CVE-2021-40847
NETGEAR Circle Parental Control Service Root RCE via MitM Attack
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.

INFO

Published Date :

Sept. 21, 2021, 6:15 p.m.

Last Modified :

Nov. 21, 2024, 6:24 a.m.

Remotely Exploitable :

Yes !

Impact Score :

5.9

Exploitability Score :

2.2
Public PoC/Exploit Available at Github

CVE-2021-40847 has a 2 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

Affected Products

The following products are affected by CVE-2021-40847 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Netgear r6700_firmware
2 Netgear r6900_firmware
3 Netgear r6900p_firmware
4 Netgear r7000_firmware
5 Netgear r7000p_firmware
6 Netgear r6400v2_firmware
7 Netgear r6700v3_firmware
8 Netgear r7850_firmware
9 Netgear r7900_firmware
10 Netgear r8000_firmware
11 Netgear rs400_firmware
12 Netgear r7000
13 Netgear r6700
14 Netgear r6900
15 Netgear r7900
16 Netgear r8000
17 Netgear r6900p
18 Netgear r7000p
19 Netgear r6400v2
20 Netgear r6700v3
21 Netgear r7850
22 Netgear rs400
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-40847.

URL Resource
https://blog.grimm-co.com/2021/09/mama-always-told-me-not-to-trust.html Exploit Third Party Advisory
https://kb.netgear.com/000064039/Security-Advisory-for-Remote-Code-Execution-on-Some-Routers-PSV-2021-0204 Vendor Advisory
https://blog.grimm-co.com/2021/09/mama-always-told-me-not-to-trust.html Exploit Third Party Advisory
https://kb.netgear.com/000064039/Security-Advisory-for-Remote-Code-Execution-on-Some-Routers-PSV-2021-0204 Vendor Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

None

Updated: 2 months ago
1 stars 0 fork 0 watcher
Born at : Feb. 14, 2023, 7:16 p.m. This repo has been linked 4 different CVEs too.

None

Updated: 1 month ago
102 stars 22 fork 22 watcher
Born at : Sept. 27, 2021, 7:35 a.m. This repo has been linked 4 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-40847 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-40847 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference https://blog.grimm-co.com/2021/09/mama-always-told-me-not-to-trust.html
    Added Reference https://kb.netgear.com/000064039/Security-Advisory-for-Remote-Code-Execution-on-Some-Routers-PSV-2021-0204
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Initial Analysis by [email protected]

    Oct. 07, 2021

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:N/AC:M/Au:N/C:C/I:C/A:C)
    Added CVSS V3.1 NIST AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
    Changed Reference Type https://blog.grimm-co.com/2021/09/mama-always-told-me-not-to-trust.html No Types Assigned https://blog.grimm-co.com/2021/09/mama-always-told-me-not-to-trust.html Exploit, Third Party Advisory
    Changed Reference Type https://kb.netgear.com/000064039/Security-Advisory-for-Remote-Code-Execution-on-Some-Routers-PSV-2021-0204 No Types Assigned https://kb.netgear.com/000064039/Security-Advisory-for-Remote-Code-Execution-on-Some-Routers-PSV-2021-0204 Vendor Advisory
    Added CWE NIST CWE-319
    Added CPE Configuration AND OR *cpe:2.3:o:netgear:r6400v2_firmware:1.0.4.106:*:*:*:*:*:*:* OR cpe:2.3:h:netgear:r6400v2:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netgear:r6700_firmware:1.0.2.16:*:*:*:*:*:*:* OR cpe:2.3:h:netgear:r6700:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netgear:r6700v3_firmware:1.0.4.106:*:*:*:*:*:*:* OR cpe:2.3:h:netgear:r6700v3:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netgear:r6900_firmware:1.0.2.16:*:*:*:*:*:*:* OR cpe:2.3:h:netgear:r6900:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netgear:r6900p_firmware:1.3.2.134:*:*:*:*:*:*:* OR cpe:2.3:h:netgear:r6900p:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netgear:r7000_firmware:1.0.11.123:*:*:*:*:*:*:* OR cpe:2.3:h:netgear:r7000:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netgear:r7000p_firmware:1.3.2.134:*:*:*:*:*:*:* OR cpe:2.3:h:netgear:r7000p:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netgear:r7850_firmware:1.0.5.68:*:*:*:*:*:*:* OR cpe:2.3:h:netgear:r7850:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netgear:r7900_firmware:1.0.4.38:*:*:*:*:*:*:* OR cpe:2.3:h:netgear:r7900:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netgear:r8000_firmware:1.0.4.68:*:*:*:*:*:*:* OR cpe:2.3:h:netgear:r8000:-:*:*:*:*:*:*:*
    Added CPE Configuration AND OR *cpe:2.3:o:netgear:rs400_firmware:1.5.0.68:*:*:*:*:*:*:* OR cpe:2.3:h:netgear:rs400:-:*:*:*:*:*:*:*
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-40847 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.40 }} -0.29%

score

0.73128

percentile

CVSS31 - Vulnerability Scoring System
Attack Vector
Attack Complexity
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Scope
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