Security readout for executives and security teams
Plain-English summary
CVE-2018-21112 is a post-authentication command injection flaw in specific NETGEAR routers and modem routers. An attacker already authenticated with high privileges and on an adjacent network could potentially run commands on the device. The affected products are older firmware builds for D7800, R7500v2, R7800, R8900, and R9000.
Executive priority
Treat this as a targeted remediation item for legacy NETGEAR network devices. It is not documented as actively exploited in the provided sources, but successful abuse could fully compromise an affected router once high-privilege access is obtained.
Technical view
The CVE describes authenticated command injection with CVSS 3.0 score 6.8. The vector is adjacent network, low complexity, high privileges required, no user interaction, and high confidentiality, integrity, and availability impact. Fixed version thresholds are listed for each affected NETGEAR model.
Likely exposure
Exposure is most likely where listed NETGEAR devices remain deployed with firmware older than the fixed versions, especially if administrative access is reachable from local or adjacent networks.
Exploitation context
The provided sources do not show CISA KEV listing or confirmed active exploitation. Risk depends heavily on whether an attacker can authenticate with high privileges and reach the affected management surface.
Researcher notes
The source bundle provides affected models, fixed firmware thresholds, CVSS vector, and vendor advisory reference. It does not identify a CWE, vulnerable endpoint, exploit maturity, or detailed mitigation beyond fixed versions.
Mitigation direction
- Upgrade D7800 firmware to 1.0.1.44 or later.
- Upgrade R7500v2 firmware to 1.0.3.38 or later.
- Upgrade R7800 firmware to 1.0.2.52 or later.
- Upgrade R8900 and R9000 firmware to 1.0.4.12 or later.
- Restrict router administration to trusted networks and accounts.
- Check current NETGEAR guidance before applying operational changes.
Validation and detection
- Inventory NETGEAR D7800, R7500v2, R7800, R8900, and R9000 devices.
- Compare installed firmware against the fixed version thresholds.
- Confirm administrative interfaces are not broadly reachable.
- Review device configuration and admin accounts for unexpected changes.
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.
Execution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2018-21112 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/000060439/Security-Advisory-for-Post-Authentication-Command-Injection-on-Some-Routers-and-Modem-Routers-PSV-2018-0093CVE 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.