Security readout for executives and security teams
Plain-English summary
This CVE affects several NETGEAR routers and gateways. A highly privileged, authenticated user on an adjacent network could trigger a stack buffer overflow, potentially causing serious device compromise. The main business risk is unmanaged network equipment running old firmware.
Executive priority
Treat as a targeted infrastructure hygiene issue. Prioritize sites with legacy NETGEAR routers, shared admin credentials, or weak management-network separation. Upgrade or isolate affected devices before routine maintenance windows where feasible.
Technical view
CVE-2018-21187 is a post-authentication stack-based buffer overflow in specified NETGEAR devices before listed firmware versions. CVSS 3.0 is 6.8 with adjacent-network attack vector, low complexity, high privileges required, no user interaction, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is likely limited to listed NETGEAR models still below fixed firmware: D7800, R7500, R7500v2, R7800, R9000, WNDR3700v4, WNDR4300, WNDR4300v2, WNDR4500v3, and WNR2000v5.
Exploitation context
The bundle does not show CISA KEV listing or active exploitation evidence. Exploitation requires an authenticated user with high privileges and adjacent-network access, which reduces broad exposure but remains serious for compromised admin accounts or shared management networks.
Researcher notes
Public detail in the bundle is sparse: no CWE entry, vulnerable handler, proof-of-concept status, or endpoint details are provided. Assessment should stay firmware- and exposure-focused unless NETGEAR guidance supplies deeper technical indicators.
Mitigation direction
- Inventory listed NETGEAR models and record current firmware versions.
- Upgrade affected devices to the fixed firmware versions named by NETGEAR or later.
- Restrict router administration access to trusted management networks only.
- Review NETGEAR advisory guidance before applying environment-specific controls.
Validation and detection
- Compare each device model and firmware version against the CVE affected-version list.
- Confirm administrative interfaces are not reachable from untrusted adjacent networks.
- Check for unexpected administrator accounts or recent configuration changes.
- Document devices that cannot be upgraded and track compensating controls.
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-2018-21187 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
- Medium
- CVSS
- 6.8 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AC:L/AV:A/A:H/C:H/I:H/PR:H/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:H/S:U/UI:N0.95.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
6.8MediumVector: CVSS:3.0/AC:L/AV:A/A:H/C:H/I:H/PR:H/S:U/UI:N
Source materials
- CVE List V5 sourceCVE List V5
- https://kb.netgear.com/000055170/Security-Advisory-for-Post-Authentication-Stack-Overflow-on-Some-Routers-and-Gateways-PSV-2017-2608CVE 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.