Security readout for executives and security teams
Plain-English summary
CVE-2018-21223 is a high-severity pre-authentication buffer overflow affecting multiple NETGEAR routers and gateways on older firmware. An unauthenticated attacker on an adjacent network could cause severe confidentiality, integrity, and availability impact. The provided sources do not show confirmed active exploitation.
Executive priority
Treat as a priority for environments using the listed NETGEAR routers or gateways. The issue is high impact but not KEV-listed in the provided data. Focus on fast inventory, firmware verification, and vendor-guided updates rather than emergency incident response without exploitation evidence.
Technical view
The CVE describes an unauthenticated buffer overflow in specified NETGEAR device firmware versions before vendor-listed fixed releases. CVSS 3.0 is 8.8 with adjacent-network attack vector, low complexity, no privileges, no user interaction, and high CIA impact. No CWE detail is provided in the bundle.
Likely exposure
Exposure is limited to the listed NETGEAR D3600, D6000, D7800, R6100, R7500, R7500v2, R9000, WNDR3700v4, WNDR4300, WNDR4300v2, WNDR4500v3, and WNR2000v5 devices running firmware older than the fixed versions.
Exploitation context
The source bundle marks this CVE as not in CISA KEV and provides no cited evidence of exploitation in the wild. Risk remains meaningful because the flaw is unauthenticated, low-complexity, and high-impact, but the available evidence only supports adjacent-network exposure.
Researcher notes
The bundle lacks CWE detail, endpoint detail, proof-of-concept status, and exploit telemetry. Analysis should stay anchored to NETGEAR PSV-2017-2457 and CVE metadata. Do not assume internet-reachable exploitation from the CVSS vector, which indicates adjacent-network access.
Mitigation direction
- Review NETGEAR advisory PSV-2017-2457 for model-specific fixed firmware.
- Upgrade affected devices to the listed fixed version or later.
- Inventory listed NETGEAR models and record current firmware versions.
- Replace devices that cannot receive vendor-supported fixed firmware.
- Follow vendor guidance before applying compensating controls.
Validation and detection
- Confirm whether any listed NETGEAR models are present in the environment.
- Compare installed firmware against the fixed versions named in the CVE description.
- Document devices below fixed firmware as vulnerable.
- Verify remediation by rechecking firmware after updates.
- Monitor vendor advisory updates for changed guidance.
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-2018-21223 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/000055114/Security-Advisory-for-Pre-Authentication-Buffer-Overflow-on-Some-Routers-and-Gateways-PSV-2017-2457CVE 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.