Security readout for executives and security teams
Plain-English summary
CVE-2018-21206 is a high-severity flaw in multiple NETGEAR routers, gateways, and extenders. An unauthenticated attacker on an adjacent network could trigger a stack-based buffer overflow, with potential confidentiality, integrity, and availability impact. No active exploitation is cited in the provided sources.
Executive priority
Prioritize remediation for exposed branch, guest, and shared-network devices. This is not marked as known exploited in the provided bundle, but the pre-authenticated impact and common device role make stale firmware a meaningful operational risk.
Technical view
The CVSS 3.0 vector is AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H, scoring 8.8. The issue affects specified NETGEAR firmware versions before the fixed releases listed in the CVE description. The bundle identifies a pre-authentication stack overflow but provides no CWE, exploit detail, or proof-of-concept evidence.
Likely exposure
Exposure is most likely where the listed NETGEAR models remain in use with firmware below the named fixed versions, especially on networks where untrusted adjacent access is possible. The provided record does not support broad internet-exposure claims.
Exploitation context
The provided sources support unauthenticated, low-complexity exploitation from an adjacent network, with no user interaction required. CISA KEV status is false in the bundle, and no cited source states active exploitation.
Researcher notes
The source bundle is limited to the CVE data and NETGEAR advisory reference. It does not provide exploit artifacts, CWE mapping, or operational mitigations beyond firmware version boundaries. Treat affected model and firmware matching as the primary validation path.
Mitigation direction
- Inventory the listed NETGEAR models across offices, labs, and remote sites.
- Upgrade affected devices to the fixed firmware version listed for each model or later.
- Check the NETGEAR advisory and support pages for current firmware guidance.
- Restrict untrusted access to local networks where these devices are reachable.
- Replace unsupported devices if fixed firmware is unavailable.
Validation and detection
- Match device model numbers against the CVE affected model list.
- Record current firmware versions and compare them to the listed fixed versions.
- Confirm whether untrusted users can reach the device from adjacent networks.
- Verify upgraded devices report the expected fixed firmware version or later.
- Document exceptions where devices cannot be patched or replaced immediately.
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-2018-21206 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/000055143/Security-Advisory-for-Pre-Authentication-Stack-Overflow-on-Some-Routers-Gateways-and-Extenders-PSV-2017-2567CVE 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.