How severe is CVE-2021-38521?

CVE-2021-38521 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity high, and availability low.

Is CVE-2021-38521 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-38521?

CVE-2021-38521 primarily affects Netgear R6400 Firmware. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-38521?

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

When was CVE-2021-38521 published?

CVE-2021-38521 was published on 2021-08-11 and last updated on 2026-06-17.

CVE-2021-38521

CVE-2021-38521 is a medium-severity vulnerability in Netgear R6400 Firmware with a CVSS 3.x base score of 6.1. 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 6.1)
CVSS v2: 6.5
EPSS exploit prediction: 1% (54th 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 1.0.1.50, R7900P before 1.4.1.50, R8000P before 1.4.1.50, RAX75 before 1.0.1.62, and RAX80 before 1.0.1.62.

Frequently asked questions

What is CVE-2021-38521?: Certain NETGEAR devices are affected by command injection by an authenticated user. This affects R6400 before 1.0.1.50, R7900P before 1.4.1.50, R8000P before 1.4.1.50, RAX75 before 1.0.1.62, and RAX80 before 1.0.1.62.
How severe is CVE-2021-38521?: CVE-2021-38521 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity high, and availability low.
Is CVE-2021-38521 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-38521?: CVE-2021-38521 primarily affects Netgear R6400 Firmware. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-38521?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-38521 published?: CVE-2021-38521 was published on 2021-08-11 and last updated on 2026-06-17.

References

https://kb.netgear.com/000063764/Security-Advisory-for-Post-Authentication-Command-Injection-on-Some-Routers-PSV-2018-0566

Affected products (5)

cpe:2.3:o:netgear:r6400_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r7900p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r8000p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:rax75_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:rax80_firmware:*:*:*:*:*:*:*:*

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