CVE-2018-21156

CVE-2018-21156 is a high-severity vulnerability in Netgear D6220 Firmware with a CVSS 3.x base score of 7.2. 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-120.

Key facts

Description

Certain NETGEAR devices are affected by a buffer overflow by an authenticated user. This affects D6220 before 1.0.0.38, D6400 before 1.0.0.74, D7000v2 before 1.0.0.74, D8500 before 1.0.3.39, DGN2200v4 before 1.0.0.102, DGN2200Bv4 before 1.0.0.102, EX3700 before 1.0.0.70, EX3800 before 1.0.0.70, EX6000 before 1.0.0.30, EX6100 before 1.0.2.22, EX6120 before 1.0.0.40, EX6130 before 1.0.0.22, EX6150 before 1.0.0.38, EX6200 before 1.0.3.86, EX7000 before 1.0.0.64, R6250 before 1.0.4.20, R6300v2 before 1.0.4.22, R6400 before 1.0.1.32, R6400v2 before 1.0.2.52, R6700 before 1.0.1.44, R6900 before 1.0.1.44, R6900P before 1.3.0.18, R7000 before 1.0.9.28, R7000P before 1.3.0.18, R7300DST before 1.0.0.62, R7900 before 1.0.2.10, R7900P before 1.3.0.10, R8000 before 1.0.4.12, R8000P before 1.3.0.10, R8300 before 1.0.2.116, R8500 before 1.0.2.116, WN2500RPv2 before 1.0.1.52, WNDR3400v3 before 1.0.1.18, and WNR3500Lv2 before 1.2.0.46.

Frequently asked questions

What is CVE-2018-21156?
Certain NETGEAR devices are affected by a buffer overflow by an authenticated user. This affects D6220 before 1.0.0.38, D6400 before 1.0.0.74, D7000v2 before 1.0.0.74, D8500 before 1.0.3.39, DGN2200v4 before 1.0.0.102, DGN2200Bv4 before 1.0.0.102, EX3700 before 1.0.0.70, EX3800 before 1.0.0.70, EX6000 before 1.0.0.30, EX6100 before 1.0.2.22, EX6120 before 1.0.0.40, EX6130 before 1.0.0.22, EX6150 before 1.0.0.38, EX6200 before 1.0.3.86, EX7000 before 1.0.0.64, R6250 before 1.0.4.20, R6300v2 before 1.0.4.22, R6400 before 1.0.1.32, R6400v2 before 1.0.2.52, R6700 before 1.0.1.44, R6900 before 1.0.1.44, R6900P before 1.3.0.18, R7000 before 1.0.9.28, R7000P before 1.3.0.18, R7300DST before 1.0.0.62, R7900 before 1.0.2.10, R7900P before 1.3.0.10, R8000 before 1.0.4.12, R8000P before 1.3.0.10, R8300 before 1.0.2.116, R8500 before 1.0.2.116, WN2500RPv2 before 1.0.1.52, WNDR3400v3 before 1.0.1.18, and WNR3500Lv2 before 1.2.0.46.
How severe is CVE-2018-21156?
CVE-2018-21156 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-21156 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-21156?
CVE-2018-21156 primarily affects Netgear D6220 Firmware. In total, 33 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-21156?
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-2018-21156 published?
CVE-2018-21156 was published on 2020-04-27 and last updated on 2026-06-17.

References

Affected products (33)

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