CVE-2018-21135
CVE-2018-21135 is a high-severity vulnerability in Netgear R6700 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-787.
Key facts
- Severity: High (CVSS 3.x base score 7.2)
- CVSS v2: 6.5
- EPSS exploit prediction: 1% (68th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Netgear R6700 Firmware
- Published:
- Last modified:
Description
Certain NETGEAR devices are affected by a stack-based buffer overflow by an authenticated user. This affects R6700 before 1.0.1.48, R7500 before 1.0.0.124, R7800 before 1.0.2.58, R8900 before 1.0.4.2, R9000 before 1.0.4.2, WNDR3700v4 before 1.0.2.102, WNDR4300v1 before 1.0.2.104, WNDR4300v2 before 1.0.0.56, WNDR4500v3 before 1.0.0.56, and WNR2000v5-R2000 before 1.0.0.68.
Frequently asked questions
- What is CVE-2018-21135?
- Certain NETGEAR devices are affected by a stack-based buffer overflow by an authenticated user. This affects R6700 before 1.0.1.48, R7500 before 1.0.0.124, R7800 before 1.0.2.58, R8900 before 1.0.4.2, R9000 before 1.0.4.2, WNDR3700v4 before 1.0.2.102, WNDR4300v1 before 1.0.2.104, WNDR4300v2 before 1.0.0.56, WNDR4500v3 before 1.0.0.56, and WNR2000v5-R2000 before 1.0.0.68.
- How severe is CVE-2018-21135?
- CVE-2018-21135 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-2018-21135 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-2018-21135?
- CVE-2018-21135 primarily affects Netgear R6700 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-2018-21135?
- 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-2018-21135 published?
- CVE-2018-21135 was published on 2020-04-23 and last updated on 2026-06-17.
References
Affected products (9)
- cpe:2.3:o:netgear:r6700_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:wndr3700_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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