How severe is CVE-2021-20174?

CVE-2021-20174 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-20174 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20174?

CVE-2021-20174 affects Netgear R6700 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-20174?

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-2021-20174 published?

CVE-2021-20174 was published on 2021-12-30 and last updated on 2026-06-17.

CVE-2021-20174

CVE-2021-20174 is a high-severity vulnerability in Netgear R6700 Firmware with a CVSS 3.x base score of 7.5. 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-319.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-319
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 utilize secure communication methods to the web interface. By default, all communication to/from the device's web interface is sent via HTTP, which causes potentially sensitive information (such as usernames and passwords) to be transmitted in cleartext.

Frequently asked questions

What is CVE-2021-20174?: Netgear Nighthawk R6700 version 1.0.4.120 does not utilize secure communication methods to the web interface. By default, all communication to/from the device's web interface is sent via HTTP, which causes potentially sensitive information (such as usernames and passwords) to be transmitted in cleartext.
How severe is CVE-2021-20174?: CVE-2021-20174 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-20174 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20174?: CVE-2021-20174 affects Netgear R6700 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-20174?: 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-2021-20174 published?: CVE-2021-20174 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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