Security readout for executives and security teams
Plain-English summary
CVE-2018-21173 is a post-authentication stack buffer overflow affecting several NETGEAR router models. An attacker would already need authenticated, high-privilege access, but successful exploitation could seriously affect confidentiality, integrity, and availability of the device.
Executive priority
Treat this as a moderate-priority infrastructure hygiene issue. It is not reported as actively exploited in the provided sources, but affected internet-edge hardware should not remain on vulnerable firmware.
Technical view
The CVE describes a stack-based buffer overflow reachable by an authenticated user on specified NETGEAR router firmware versions. CVSS 3.0 score is 6.8 with adjacent attack vector, low complexity, high privileges required, no user interaction, and high CIA impact.
Likely exposure
Exposure is most likely in environments still running affected NETGEAR models before the fixed firmware versions listed in the CVE description and vendor advisory.
Exploitation context
The provided sources do not show CISA KEV listing or active exploitation. Risk is reduced by the high-privilege authentication requirement, but compromised admin credentials or insider access could make impact significant.
Researcher notes
Affected models named are R7500, R7800, R9000, WNDR3700v4, WNDR4300, WNDR4300v2, WNDR4500v3, and WNR2000v5 before specified firmware versions. The source bundle does not provide CWE details, exploit artifacts, or deeper root-cause analysis.
Mitigation direction
- Identify any listed NETGEAR router models in use.
- Upgrade affected routers to NETGEAR's fixed firmware versions or later.
- Follow the NETGEAR advisory for model-specific remediation guidance.
- Restrict router administration to trusted administrators and management networks.
- Replace unsupported devices if fixed firmware is unavailable.
Validation and detection
- Inventory router model names and current firmware versions.
- Compare firmware against the fixed versions listed in the CVE description.
- Confirm administrative access is limited to authorized users.
- Review vendor advisory status for each deployed model.
- Document remediation or replacement decisions for remaining affected devices.
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-2018-21173 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/000055185/Security-Advisory-for-Post-Authentication-Stack-Overflow-on-Some-Routers-PSV-2017-2627CVE 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.