Rax35 FirmwareOperating system · Netgear

CVE-2021-38526

HIGH · 7.5 CVSS v3.1 Published 2021-08-11
Fix available
A fix is available. Upgrade to 1.0.3.94 or later.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges 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
Certain NETGEAR devices are affected by a buffer overflow by an unauthenticated attacker. This affects RAX35 before 1.0.3.94, RAX38 before 1.0.3.94, and RAX40 before 1.0.3.94.

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

Unauthenticated remote buffer overflow vulnerability in the web management interface of NETGEAR RAX35, RAX38, and RAX40 routers. An attacker can exploit this to execute arbitrary code or cause denial of service without authentication, likely through malformed HTTP requests to vulnerable form handlers.

MitigationUpgrade NETGEAR router firmware to version 1.0.3.94 or later for the affected models (RAX35, RAX38, RAX40). If upgrading is not immediately possible, restrict administrative interface access to trusted networks or disable remote administration.

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

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Rax35 FirmwareOperating system
Affected:< 1.0.3.94
Rax38 FirmwareOperating system
Affected:< 1.0.3.94
Rax40 FirmwareOperating system
Affected:< 1.0.3.94

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
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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. Identify the router model
    Check the device label on the router or log into the admin interface and look for the model number (typically displayed on the main status page or at the top of the administration panel)
    Affected if The model is RAX35, RAX38, or RAX40 (other models are not affected by this CVE)
  2. Check the installed firmware version
    In the web admin interface, navigate to the Firmware Update or Administration section and locate the current firmware version displayed. Alternatively, some NETGEAR routers display the version on the login page or in the router status overview
    Affected if The firmware version is below 1.0.3.94 (versions 1.0.3.94 and later are patched)
  3. Verify web management interface accessibility
    Attempt to access the router web interface by entering the router IP address in a web browser (commonly http://192.168.1.1 or http://routerlogin.net). Confirm the interface loads and is reachable
    Affected if The web management interface is accessible (this is required for the vulnerability to be exploitable, though it is unauthenticated so no login is needed to trigger the flaw)

You are affected if you are running a RAX35, RAX38, or RAX40 router with firmware version earlier than 1.0.3.94 and the web management interface is reachable on your network.

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.

dbcve · scoped
Upgrade available Upgrade to 1.0.3.94 or later
Fixed in 1.0.3.94
Interim mitigation

Upgrade NETGEAR router firmware to version 1.0.3.94 or later for the affected models (RAX35, RAX38, RAX40). If upgrading is not immediately possible, restrict administrative interface access to trusted networks or disable remote administration.

Recommended fix High confidence

Firmware version 1.0.3.94 or later for RAX35, RAX38, and RAX40

  1. 1. Visit the NETGEAR support website at kb.netgear.com
  2. 2. Search for your router model (RAX35, RAX38, or RAX40)
  3. 3. Navigate to the Downloads/Firmware section
  4. 4. Download firmware version 1.0.3.94 or later
  5. 5. Access your router's web management interface
  6. 6. Navigate to the Advanced > Administration > Firmware Update section
  7. 7. Upload and install the downloaded firmware file
  8. 8. Wait for the router to reboot and verify the new firmware version

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Rax35 Firmware Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing1.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,090
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,744.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-38526 — 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-2021-38526 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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