How severe is CVE-2018-21157?

CVE-2018-21157 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-21157 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-21157?

CVE-2018-21157 primarily affects Netgear D7800 Firmware. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-21157?

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

When was CVE-2018-21157 published?

CVE-2018-21157 was published on 2020-04-27 and last updated on 2026-06-17.

CVE-2018-21157

CVE-2018-21157 is a medium-severity vulnerability in Netgear D7800 Firmware with a CVSS 3.x base score of 6.8. 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-78.

Key facts

Severity: Medium (CVSS 3.x base score 6.8)
CVSS v2: 5.2
EPSS exploit prediction: 1% (55th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Netgear D7800 Firmware
Published: 2020-04-27
Last modified: 2026-06-17

Description

Certain NETGEAR devices are affected by command injection by an authenticated user. This affects D7800 before 1.0.1.28, R6700 before 1.0.1.44, R6900 before 1.0.1.44, R7000 before 1.0.9.28, R7500v2 before 1.0.3.24, R7800 before 1.0.2.38, R9000 before 1.0.2.52, WNDR4300v2 before 1.0.0.50, and WNDR4500v3 before 1.0.0.50.

Frequently asked questions

What is CVE-2018-21157?: Certain NETGEAR devices are affected by command injection by an authenticated user. This affects D7800 before 1.0.1.28, R6700 before 1.0.1.44, R6900 before 1.0.1.44, R7000 before 1.0.9.28, R7500v2 before 1.0.3.24, R7800 before 1.0.2.38, R9000 before 1.0.2.52, WNDR4300v2 before 1.0.0.50, and WNDR4500v3 before 1.0.0.50.
How severe is CVE-2018-21157?: CVE-2018-21157 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-21157 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-21157?: CVE-2018-21157 primarily affects Netgear D7800 Firmware. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-21157?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-21157 published?: CVE-2018-21157 was published on 2020-04-27 and last updated on 2026-06-17.

References

https://kb.netgear.com/000059473/Security-Advisory-for-Post-Authentication-Command-Injection-on-Some-Gateways-and-Routers-PSV-2017-2248

Affected products (9)

cpe:2.3:o:netgear:d7800_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r6700_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r6900_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r7000_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r7500_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r7800_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r9000_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:wndr4300_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:wndr4500_firmware:*:*:*:*:*:*:*:*

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