CVE-2021-23147

Root command execution via unauthenticated UART console

Published Dec 30, 2021 · Updated Aug 3, 2024

Improper authentication in the NETGEAR Nighthawk R6700v3 1.0.4.120 UART console allows physically proximate attackers to execute commands as root. The production firmware leaves the serial UART console enabled without enforcing the device authentication used by other management interfaces. Physical access and a serial connection are required; successful access grants an unauthenticated root command shell with full device control.

CVSS severity6.8
Medium
EPSS probability0.36%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authentication in the NETGEAR Nighthawk R6700v3 1.0.4.120 UART console allows physically proximate attackers to execute commands as root. The production firmware leaves the serial UART console enabled without enforcing the device authentication used by other management interfaces. Physical access and a serial connection are required; successful access grants an unauthenticated root command shell with full device control.

The record

CVE
CVE-2021-23147
Published
Dec 30, 2021
Updated
Aug 3, 2024
Vendor
NETGEAR
Product
Nighthawk AC1750 Smart WiFi Router (R6700v3)
Classifications
CWE-287, T1059.008
Attack vector
physical
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 30, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.0.4.120

What conditions does exploitation require?

Attack vectorphysical
Required privilegesunauthenticated

What is affected?

NETGEAR · Nighthawk AC1750 Smart WiFi Router (R6700v3)version=1.0.4.120

Published CVSS scores

7.2NIST NVDAV:L/AC:L/Au:N/C:C/I:C/A:C
6.8NIST NVDCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorphysical
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-287Improper Authentication
T1059.008Command and Scripting Interpreter: Network Device CLI

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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