How severe is CVE-2021-45637?

CVE-2021-45637 has a CVSS 3.x base score of 8.3, rated high 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 low.

Is CVE-2021-45637 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-45637?

CVE-2021-45637 primarily affects Netgear R6260 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-2021-45637?

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-2021-45637 published?

CVE-2021-45637 was published on 2021-12-26 and last updated on 2026-06-17.

CVE-2021-45637

CVE-2021-45637 is a high-severity vulnerability in Netgear R6260 Firmware with a CVSS 3.x base score of 8.3. 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-787.

Key facts

Severity: High (CVSS 3.x base score 8.3)
CVSS v2: 7.5
EPSS exploit prediction: 1% (64th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Netgear R6260 Firmware
Published: 2021-12-26
Last modified: 2026-06-17

Description

Certain NETGEAR devices are affected by a stack-based buffer overflow by an unauthenticated attacker. This affects R6260 before 1.1.0.76, R6800 before 1.2.0.62, R6700v2 before 1.2.0.62, R6900v2 before 1.2.0.62, R7450 before 1.2.0.62, AC2100 before 1.2.0.62, AC2400 before 1.2.0.62, and AC2600 before 1.2.0.62.

Frequently asked questions

What is CVE-2021-45637?: Certain NETGEAR devices are affected by a stack-based buffer overflow by an unauthenticated attacker. This affects R6260 before 1.1.0.76, R6800 before 1.2.0.62, R6700v2 before 1.2.0.62, R6900v2 before 1.2.0.62, R7450 before 1.2.0.62, AC2100 before 1.2.0.62, AC2400 before 1.2.0.62, and AC2600 before 1.2.0.62.
How severe is CVE-2021-45637?: CVE-2021-45637 has a CVSS 3.x base score of 8.3, rated high 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 low.
Is CVE-2021-45637 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-45637?: CVE-2021-45637 primarily affects Netgear R6260 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-2021-45637?: 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-2021-45637 published?: CVE-2021-45637 was published on 2021-12-26 and last updated on 2026-06-17.

References

https://kb.netgear.com/000064059/Security-Advisory-for-Pre-Authentication-Stack-Overflow-on-Some-Routers-PSV-2019-0081

Affected products (8)

cpe:2.3:o:netgear:r6260_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r6800_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r6700v2_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r6900v2_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r7450_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:ac2100_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:ac2400_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:ac2600_firmware:*:*:*:*:*:*:*:*

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