How severe is CVE-2021-45631?

CVE-2021-45631 has a CVSS 3.x base score of 9.6, rated critical severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-45631 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-45631?

CVE-2021-45631 primarily affects Netgear Cbr40 Firmware. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-45631?

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

When was CVE-2021-45631 published?

CVE-2021-45631 was published on 2021-12-26 and last updated on 2026-06-17.

CVE-2021-45631

CVE-2021-45631 is a critical-severity vulnerability in Netgear Cbr40 Firmware with a CVSS 3.x base score of 9.6. 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: Critical (CVSS 3.x base score 9.6)
CVSS v2: 5.8
EPSS exploit prediction: 1% (58th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-77
Affected product: Netgear Cbr40 Firmware
Published: 2021-12-26
Last modified: 2026-06-17

Description

Certain NETGEAR devices are affected by command injection by an unauthenticated attacker. This affects CBR40 before 2.5.0.24, CBR750 before 4.6.3.6, RBK752 before 3.2.17.12, RBR750 before 3.2.17.12, RBS750 before 3.2.17.12, RBK852 before 3.2.17.12, RBR850 before 3.2.17.12, and RBS850 before 3.2.17.12.

Frequently asked questions

What is CVE-2021-45631?: Certain NETGEAR devices are affected by command injection by an unauthenticated attacker. This affects CBR40 before 2.5.0.24, CBR750 before 4.6.3.6, RBK752 before 3.2.17.12, RBR750 before 3.2.17.12, RBS750 before 3.2.17.12, RBK852 before 3.2.17.12, RBR850 before 3.2.17.12, and RBS850 before 3.2.17.12.
How severe is CVE-2021-45631?: CVE-2021-45631 has a CVSS 3.x base score of 9.6, rated critical severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-45631 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-45631?: CVE-2021-45631 primarily affects Netgear Cbr40 Firmware. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-45631?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-45631 published?: CVE-2021-45631 was published on 2021-12-26 and last updated on 2026-06-17.

References

https://kb.netgear.com/000064136/Security-Advisory-for-Pre-Authentication-Command-Injection-on-Some-WiFi-Systems-PSV-2020-0504

Affected products (8)

cpe:2.3:o:netgear:cbr40_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:cbr750_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:rbk752_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:rbr750_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:rbs750_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:rbk852_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:rbr850_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:rbs850_firmware:*:*:*:*:*:*:*:*

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