How severe is CVE-2021-23147?

CVE-2021-23147 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over physical access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-23147 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (30th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-23147?

CVE-2021-23147 affects Netgear R6700 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-23147?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-23147 published?

CVE-2021-23147 was published on 2021-12-30 and last updated on 2026-06-17.

CVE-2021-23147

CVE-2021-23147 is a medium-severity vulnerability in Netgear R6700 Firmware with a CVSS 3.x base score of 6.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: Medium (CVSS 3.x base score 6.8)
CVSS v2: 7.2
EPSS exploit prediction: 0% (30th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Netgear R6700 Firmware
Published: 2021-12-30
Last modified: 2026-06-17

Description

Netgear Nighthawk R6700 version 1.0.4.120 does not have sufficient protections for the UART console. A malicious actor with physical access to the device is able to connect to the UART port via a serial connection and execute commands as the root user without authentication.

Frequently asked questions

What is CVE-2021-23147?: Netgear Nighthawk R6700 version 1.0.4.120 does not have sufficient protections for the UART console. A malicious actor with physical access to the device is able to connect to the UART port via a serial connection and execute commands as the root user without authentication.
How severe is CVE-2021-23147?: CVE-2021-23147 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over physical access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-23147 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (30th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-23147?: CVE-2021-23147 affects Netgear R6700 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-23147?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-23147 published?: CVE-2021-23147 was published on 2021-12-30 and last updated on 2026-06-17.

References

https://www.tenable.com/security/research/tra-2021-57

Affected products (1)

cpe:2.3:o:netgear:r6700_firmware:1.0.4.120:*:*:*:*:*:*:*

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