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CVE Record

CVE-2018-21140: Certain NETGEAR devices are affected by incorrect configuration of security settings.

Certain NETGEAR devices are affected by incorrect configuration of security settings. This affects D3600 before 1.0.0.76 and D6000 before 1.0.0.76.

HighCVSS 8.8Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

CVE-2018-21140 is a high-severity NETGEAR modem router misconfiguration issue. The sources identify D3600 and D6000 devices running firmware earlier than 1.0.0.76. A successful attack could seriously affect confidentiality, integrity, and availability, but the provided evidence does not show active exploitation.

Executive priority

Prioritize remediation where these routers support business connectivity, remote sites, or shared networks. The impact rating is high, but urgency should be driven by confirmed device presence and whether untrusted adjacent-network access is possible.

Technical view

The CVE describes incorrect configuration of security settings in NETGEAR D3600 and D6000 before 1.0.0.76. CVSS 3.0 score is 8.8 with adjacent-network attack vector, low complexity, no privileges, and no user interaction, with high confidentiality, integrity, and availability impact.

Likely exposure

Exposure is limited to organizations using NETGEAR D3600 or D6000 modem routers below firmware 1.0.0.76. Risk is higher where untrusted users or compromised devices can access the same adjacent/local network as the router.

Exploitation context

The source bundle does not include exploit details, public exploit confirmation, or KEV listing. Treat this as a serious local-network exposure, not confirmed internet-wide active exploitation based on the provided evidence.

Researcher notes

The public data is sparse: no CWE is listed and affected CPEs are not populated in the bundle. The key technical anchors are NETGEAR D3600/D6000, versions before 1.0.0.76, and CVSS adjacent-network, no-auth conditions.

Mitigation direction

  • Identify any NETGEAR D3600 or D6000 modem routers in use.
  • Check current firmware versions against 1.0.0.76.
  • Apply NETGEAR vendor guidance from the linked advisory.
  • Upgrade affected devices to vendor-supported fixed firmware where available.
  • Restrict router access to trusted local network segments.
  • Replace devices if supported firmware is unavailable.

Validation and detection

  • Inventory D3600 and D6000 devices across offices and remote sites.
  • Record model, firmware version, and management exposure for each device.
  • Confirm affected devices are no longer below firmware 1.0.0.76.
  • Review network segmentation around router management access.
  • Track remediation evidence against the NETGEAR advisory.
Prepared
Confidence
medium
Sources
3

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

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

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CVE-2018-21140 mapping review

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Vulnerability profileCVE Program record
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

Official CVE source material

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.

1CVSS vectors
0Timeline events
0ADP providers
2Source links

CVSS vector scores

1 official score

We 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.

ScoreVersionSeverityVectorExploitImpactSource
8.8CVSS 3.0HighCVSS:3.0/AC:L/AV:A/A:H/C:H/I:H/PR:N/S:U/UI:N2.85.9Primary CVE score

Vulnerability scoring details

Base CVSS 3.0 score

8.8High
CVSS 3.0 vector shape for CVE-2018-21140Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.0/AC:L/AV:A/A:H/C:H/I:H/PR:N/S:U/UI:N

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
n/an/an/aListed
Weakness

CWE details

No CWE listed

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