Security readout for executives and security teams
Plain-English summary
Some NETGEAR D3600 and D6000 modem routers contain a hardcoded password in firmware versions before 1.0.0.76. An attacker with adjacent-network access could potentially compromise the device without user interaction or valid credentials, creating risk to confidentiality, integrity, and availability.
Executive priority
Treat this as a high-priority legacy network-device exposure. Prioritize confirming whether affected NETGEAR models remain deployed, because vulnerable routers can become a foothold for network compromise.
Technical view
CVE-2018-21137 is a hardcoded-password issue affecting NETGEAR D3600 and D6000 devices before firmware 1.0.0.76. The CVSS 3.0 vector is AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H, indicating adjacent-network reachability, low complexity, no privileges, no user interaction, and high impact.
Likely exposure
Exposure is most likely in environments still running NETGEAR D3600 or D6000 modem routers with firmware older than 1.0.0.76. The CVSS vector indicates adjacent-network access, so risk depends heavily on local network proximity and device placement.
Exploitation context
The provided sources do not show CISA KEV listing or other evidence of active exploitation. The issue is still serious because hardcoded credentials can undermine authentication when an attacker can reach the affected network surface.
Researcher notes
The public bundle is sparse: no CWE is listed, CPEs are not populated, and no exploit details are provided. Use the NETGEAR advisory and CVE record as authoritative sources for affected models and version boundaries.
Mitigation direction
- Identify any NETGEAR D3600 or D6000 modem routers in use.
- Check current firmware versions against NETGEAR advisory guidance.
- Update affected devices to firmware 1.0.0.76 or a later non-affected release.
- Retire or isolate devices that cannot be updated.
- Restrict management access to trusted internal networks only.
Validation and detection
- Inventory network edge and small-office modem routers by model.
- Verify D3600 and D6000 firmware versions directly from device administration pages.
- Confirm no affected device runs firmware older than 1.0.0.76.
- Review network placement for adjacent-network exposure.
- Track remediation evidence against asset records.
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.
Credential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2018-21137 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/000060223/Security-Advisory-for-Hardcoded-Password-on-Some-Modem-Routers-PSV-2018-0099CVE 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.