CVE-2021-20168

Root command execution via default UART credentials

Published Dec 30, 2021 · Updated Aug 3, 2024

Improper authentication in NETGEAR Nighthawk RAX43 1.0.3.96 allows physically proximate attackers to execute commands as root via UART. The serial console accepts the factory admin:admin credentials instead of enforcing device-specific administrative credentials. Physical access and a serial connection are required, after which the attacker obtains unrestricted command execution on the router.

CVSS severity6.8
Medium
EPSS probability0.33%
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 NETGEAR Nighthawk RAX43 1.0.3.96 allows physically proximate attackers to execute commands as root via UART. The serial console accepts the factory admin:admin credentials instead of enforcing device-specific administrative credentials. Physical access and a serial connection are required, after which the attacker obtains unrestricted command execution on the router.

The record

CVE
CVE-2021-20168
Published
Dec 30, 2021
Updated
Aug 3, 2024
Vendor
NETGEAR
Product
Nighthawk RAX43
Classifications
CWE-287, T1078.001
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=1.0.3.96

What conditions does exploitation require?

Attack vectorphysical
Required privilegesunauthenticated

What is affected?

NETGEAR · Nighthawk RAX43version=1.0.3.96

Published CVSS scores

6.8NIST National Vulnerability DatabaseCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.2NIST National Vulnerability DatabaseAV:L/AC:L/Au:N/C:C/I:C/A:C

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.

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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
T1078.001Valid Accounts: Default Accounts

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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