How severe is CVE-2021-20173?

CVE-2021-20173 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-20173 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20173?

CVE-2021-20173 affects Netgear R6700 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-20173?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-20173 published?

CVE-2021-20173 was published on 2021-12-30 and last updated on 2026-06-17.

CVE-2021-20173

CVE-2021-20173 is a high-severity vulnerability in Netgear R6700 Firmware with a CVSS 3.x base score of 8.8. 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-78.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 3% (87th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Netgear R6700 Firmware
Published: 2021-12-30
Last modified: 2026-06-17

Description

Netgear Nighthawk R6700 version 1.0.4.120 contains a command injection vulnerability in update functionality of the device. By triggering a system update check via the SOAP interface, the device is susceptible to command injection via preconfigured values.

Frequently asked questions

What is CVE-2021-20173?: Netgear Nighthawk R6700 version 1.0.4.120 contains a command injection vulnerability in update functionality of the device. By triggering a system update check via the SOAP interface, the device is susceptible to command injection via preconfigured values.
How severe is CVE-2021-20173?: CVE-2021-20173 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-20173 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20173?: CVE-2021-20173 affects Netgear R6700 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-20173?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-20173 published?: CVE-2021-20173 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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