How severe is CVE-2018-21140?

CVE-2018-21140 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2018-21140 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-21140?

CVE-2018-21140 primarily affects Netgear D3600 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-21140?

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

When was CVE-2018-21140 published?

CVE-2018-21140 was published on 2020-04-21 and last updated on 2026-06-17.

CVE-2018-21140

CVE-2018-21140 is a medium-severity vulnerability in Netgear D3600 Firmware with a CVSS 3.x base score of 6.5. 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 3.3
EPSS exploit prediction: 1% (41st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Netgear D3600 Firmware
Published: 2020-04-21
Last modified: 2026-06-17

Description

Certain NETGEAR devices are affected by incorrect configuration of security settings. This affects D3600 before 1.0.0.76 and D6000 before 1.0.0.76.

Frequently asked questions

What is CVE-2018-21140?: Certain NETGEAR devices are affected by incorrect configuration of security settings. This affects D3600 before 1.0.0.76 and D6000 before 1.0.0.76.
How severe is CVE-2018-21140?: CVE-2018-21140 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2018-21140 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-21140?: CVE-2018-21140 primarily affects Netgear D3600 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-21140?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-21140 published?: CVE-2018-21140 was published on 2020-04-21 and last updated on 2026-06-17.

References

https://kb.netgear.com/000060221/Security-Advisory-for-Security-Misconfiguration-on-Some-Modem-Routers-PSV-2018-0097

Affected products (2)

cpe:2.3:o:netgear:d3600_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:d6000_firmware:*:*:*:*:*:*:*:*

More vulnerabilities in Netgear D3600 Firmware

CVE-2018-21137 — Critical (CVSS 9.8): Certain NETGEAR devices are affected by a hardcoded password. This affects D3600 before 1.0.0.76 and D6000 before…
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