Security readout for executives and security teams
Plain-English summary
Some NETGEAR routers and gateways have a post-authentication stack overflow flaw. A user who already has high privileges and network adjacency could potentially disrupt or compromise the device. The business risk is highest where these devices protect office, remote-site, or small-business networks.
Executive priority
Treat this as a moderate-priority network infrastructure issue. Patch or replace affected devices during the next maintenance window, sooner for business-critical sites or environments with broad admin access.
Technical view
CVE-2018-21171 is a stack-based buffer overflow in specific NETGEAR devices, requiring adjacent-network access and high privileges, with no user interaction. Affected firmware includes D6100 before 1.0.0.57, R7800 before 1.0.2.40, R9000 before 1.0.3.6, WNDR3700v4 before 1.0.2.92, and WNDR4300 before 1.0.2.98.
Likely exposure
Exposure is likely limited to listed NETGEAR models running older firmware, especially where administrative access is shared, weakly governed, or reachable from local networks.
Exploitation context
The provided sources do not show active exploitation, and CISA KEV status is false. The CVSS vector indicates exploitation requires adjacent-network access and high privileges, but successful exploitation could have high confidentiality, integrity, and availability impact.
Researcher notes
Evidence is limited to CVE metadata and NETGEAR advisory references. No exploit details, affected code paths, or CWE assignment are provided in the source bundle. Avoid assuming internet-reachable exploitation unless local configuration shows it.
Mitigation direction
- Inventory listed NETGEAR models and firmware versions.
- Upgrade affected devices to the fixed firmware versions or later.
- Review the NETGEAR advisory for model-specific upgrade guidance.
- Restrict administrative access to trusted users and trusted networks.
- Replace unsupported devices if fixed firmware is unavailable.
Validation and detection
- Compare each device firmware version against the affected version thresholds.
- Confirm upgraded devices report the expected fixed firmware or later.
- Verify administrative interfaces are not exposed beyond trusted networks.
- Review administrative account access for unnecessary high-privilege users.
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-2018-21171 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/000055187/Security-Advisory-for-Post-Authentication-Stack-Overflow-on-Some-Routers-and-Gateways-PSV-2017-2632CVE 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.