How severe is CVE-2021-38520?

CVE-2021-38520 has a CVSS 3.x base score of 6.6, rated medium severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-38520 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-38520?

CVE-2021-38520 primarily affects Netgear R6400 Firmware. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-38520?

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

When was CVE-2021-38520 published?

CVE-2021-38520 was published on 2021-08-11 and last updated on 2026-06-17.

CVE-2021-38520

CVE-2021-38520 is a medium-severity vulnerability in Netgear R6400 Firmware with a CVSS 3.x base score of 6.6. 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-77.

Key facts

Severity: Medium (CVSS 3.x base score 6.6)
CVSS v2: 6.5
EPSS exploit prediction: 1% (71st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-77
Affected product: Netgear R6400 Firmware
Published: 2021-08-11
Last modified: 2026-06-17

Description

Certain NETGEAR devices are affected by command injection by an authenticated user. This affects R6400 before 1.0.1.52, R6400v2 before 1.0.4.84, R6700v3 before 1.0.4.84, R6700v2 before 1.2.0.62, R6900v2 before 1.2.0.62, and R7000P before 1.3.2.124.

Frequently asked questions

What is CVE-2021-38520?: Certain NETGEAR devices are affected by command injection by an authenticated user. This affects R6400 before 1.0.1.52, R6400v2 before 1.0.4.84, R6700v3 before 1.0.4.84, R6700v2 before 1.2.0.62, R6900v2 before 1.2.0.62, and R7000P before 1.3.2.124.
How severe is CVE-2021-38520?: CVE-2021-38520 has a CVSS 3.x base score of 6.6, rated medium severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-38520 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-38520?: CVE-2021-38520 primarily affects Netgear R6400 Firmware. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-38520?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-38520 published?: CVE-2021-38520 was published on 2021-08-11 and last updated on 2026-06-17.

References

https://kb.netgear.com/000063763/Security-Advisory-for-Post-Authentication-Command-Injection-on-Some-Routers-PSV-2018-0565

Affected products (4)

cpe:2.3:o:netgear:r6400_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r6700_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r6900_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r7000p_firmware:*:*:*:*:*:*:*:*

More vulnerabilities in Netgear R6400 Firmware

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