How severe is CVE-2018-21155?

CVE-2018-21155 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2018-21155 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-21155?

CVE-2018-21155 primarily affects Netgear D7800 Firmware. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-21155?

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

When was CVE-2018-21155 published?

CVE-2018-21155 was published on 2020-04-27 and last updated on 2026-06-17.

CVE-2018-21155

CVE-2018-21155 is a medium-severity vulnerability in Netgear D7800 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 4.3
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Netgear D7800 Firmware
Published: 2020-04-27
Last modified: 2026-06-17

Description

Certain NETGEAR devices are affected by stored XSS. This affects D7800 before 1.0.1.34, DM200 before 1.0.0.52, R6100 before 1.0.1.22, R7500 before 1.0.0.122, R7500v2 before 1.0.3.26, R7800 before 1.0.2.42, R8900 before 1.0.4.2, R9000 before 1.0.3.16, WNDR4300 before 1.0.2.98, WNDR4300v2 before 1.0.0.54, WNDR4500v3 before 1.0.0.54, and WNR2000v5 before 1.0.0.64.

Frequently asked questions

What is CVE-2018-21155?: Certain NETGEAR devices are affected by stored XSS. This affects D7800 before 1.0.1.34, DM200 before 1.0.0.52, R6100 before 1.0.1.22, R7500 before 1.0.0.122, R7500v2 before 1.0.3.26, R7800 before 1.0.2.42, R8900 before 1.0.4.2, R9000 before 1.0.3.16, WNDR4300 before 1.0.2.98, WNDR4300v2 before 1.0.0.54, WNDR4500v3 before 1.0.0.54, and WNR2000v5 before 1.0.0.64.
How severe is CVE-2018-21155?: CVE-2018-21155 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2018-21155 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-21155?: CVE-2018-21155 primarily affects Netgear D7800 Firmware. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-21155?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-21155 published?: CVE-2018-21155 was published on 2020-04-27 and last updated on 2026-06-17.

References

https://kb.netgear.com/000059478/Security-Advisory-for-Stored-Cross-Site-Scripting-on-Some-Gateways-and-Routers-PSV-2017-3101

Affected products (10)

cpe:2.3:o:netgear:d7800_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:dm200_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r6100_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r7500_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r7800_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r8900_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:r9000_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:wndr4300_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:wndr4500_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:netgear:wnr2000_firmware:*:*:*:*:*:*:*:*

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