OS Command InjectionWeakness · CWE-78

CVE-2026-35018

HIGH · 8.8 CVSS v3.1 Published 2026-06-23
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
94/100
Remediation priority · Urgent
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
NetComm NF20MESH routers running firmware R6B031 and earlier contain an authenticated remote code execution vulnerability that allows authenticated attackers to execute arbitrary commands as root by injecting shell metacharacters into the username JSON parameter processed by the dalStorage_addUserAccount function. Attackers can exploit the unsafe concatenation of user-supplied input into a shell command string passed to rut_doSystemAction without sanitization to achieve full root-level command execution on the underlying operating system.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Authenticated remote code execution vulnerability in NetComm NF20MESH routers (firmware R6B031 and earlier). The dalStorage_addUserAccount function insecurely concatenates user-supplied input from the username JSON parameter into a shell command passed to rut_doSystemAction, allowing authenticated attackers to inject shell metacharacters and achieve root-level command execution.

MitigationApply available firmware updates from NetComm. If no update is available, disable remote administration interfaces, enforce strict access controls, and segment affected devices from untrusted networks to reduce attack surface.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Confirm device model is NetComm NF20MESH
    Access the router web interface or check the device label/marketing materials to verify the exact model number matches NF20MESH
    Affected if Device is a NetComm NF20MESH router
  2. Check installed firmware version
    Log into the router web interface and navigate to the status or firmware upgrade page to view the current firmware version. Alternatively, check via CLI if available using 'cat /proc/version' or router-specific commands
    Affected if Firmware version is R6B031 or any version earlier than R6B031 (e.g., R6B030, R6B029, etc.)
  3. Verify if remote web administration is enabled
    Access the router administration panel, go to remote management settings, and check whether remote access (WAN-facing HTTP/HTTPS administration) is enabled
    Affected if Remote administration interface is exposed to the WAN or untrusted networks
  4. Check authentication configuration
    Review the router user account settings to determine if default credentials are in use or if weak/user-managed passwords are set for administrative access
    Affected if The device allows authenticated access with any valid credentials, enabling the attacker to reach the vulnerable function

The device is affected if it is a NetComm NF20MESH router running firmware R6B031 or earlier, and the attacker can obtain valid admin credentials to access the device either locally or remotely.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply available firmware updates from NetComm. If no update is available, disable remote administration interfaces, enforce strict access controls, and segment affected devices from untrusted networks to reduce attack surface.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA2.0 h
12.0 hours of engineering $2,180
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-35018 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-35018 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data