Security readout for executives and security teams
Plain-English summary
CVE-2018-21216 is a high-severity pre-authentication buffer overflow affecting specific older NETGEAR routers and gateways. An attacker does not need credentials or user interaction, but the CVSS vector indicates adjacent-network access. Organizations using the listed models should treat outdated firmware as urgent exposure.
Executive priority
Prioritize remediation if these NETGEAR models support business connectivity, remote sites, or shared wireless networks. The issue is old but still material when legacy firmware remains in service.
Technical view
The CVE describes an unauthenticated buffer overflow in NETGEAR D3600, D6000, D6100, and R6100 devices before specified firmware versions. CVSS 3.0 is 8.8 with low complexity, no privileges, no user interaction, adjacent attack vector, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is most likely where affected NETGEAR D3600, D6000, D6100, or R6100 devices remain deployed below the fixed firmware versions, especially on untrusted LAN, Wi-Fi, or adjacent network segments.
Exploitation context
The provided sources do not show CISA KEV listing or active exploitation evidence. The risk remains significant because the issue is unauthenticated, low-complexity, and can affect confidentiality, integrity, and availability if reachable from an adjacent network.
Researcher notes
The bundle identifies affected models and version thresholds but does not include CWE, vulnerable endpoint details, exploit maturity, or full vendor remediation text. Do not assume internet-wide exploitability from the CVSS vector; it is adjacent-network access.
Mitigation direction
- Upgrade D3600 and D6000 devices to firmware 1.0.0.67 or later.
- Upgrade D6100 devices to firmware 1.0.0.56 or later.
- Upgrade R6100 devices to firmware 1.0.1.20 or later.
- Check NETGEAR advisory PSV-2017-2485 for model-specific firmware guidance.
- Restrict access to device management interfaces from untrusted LAN or Wi-Fi segments.
Validation and detection
- Inventory networks for NETGEAR D3600, D6000, D6100, and R6100 devices.
- Record current firmware versions and compare them to the fixed version thresholds.
- Confirm whether affected devices are reachable from guest, contractor, or shared networks.
- Verify upgrade completion through the device administrative interface or asset records.
- Review available device logs for unusual administrative or stability events.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CVE-2018-21216 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 8.8 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AC:L/AV:A/A:H/C:H/I:H/PR:N/S:U/UI:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.0/AC:L/AV:A/A:H/C:H/I:H/PR:N/S:U/UI:N2.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
8.8HighVector: CVSS:3.0/AC:L/AV:A/A:H/C:H/I:H/PR:N/S:U/UI:N
Source materials
- CVE List V5 sourceCVE List V5
- https://kb.netgear.com/000055121/Security-Advisory-for-Pre-Authentication-Buffer-Overflow-on-Some-Routers-and-Gateways-PSV-2017-2485CVE reference · x_refsource_CONFIRM
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.