Cbr40 FirmwareOperating system · Netgear

CVE-2021-45598

HIGH · 8.8 CVSS v3.1 Published 2021-12-26
Fix available
A fix is available. Upgrade to 2.5.0.24 / 3.2.17.12 or later.
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
Certain NETGEAR devices are affected by command injection by an authenticated user. This affects CBR40 before 2.5.0.24, CBR750 before 4.6.3.6, RBK852 before 3.2.17.12, RBR850 before 3.2.17.12, and RBS850 before 3.2.17.12.

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

This is an authenticated command injection vulnerability affecting specific NETGEAR mesh WiFi systems and cable routers (CBR40, CBR750, RBK852, RBR850, RBS850). An authenticated attacker can execute arbitrary commands on the affected devices due to improper input sanitization, likely in a web interface or API endpoint.

MitigationUpdate firmware to the patched versions (CBR40: 2.5.0.24, CBR750: 4.6.3.6, RBK852/RBR850/RBS850: 3.2.17.12). If immediate patching is not possible, limit administrative access to trusted personnel only and monitor for suspicious activity.

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
Cbr40 FirmwareOperating system
Affected:< 2.5.0.24
Cbr750 FirmwareOperating system
Affected:< 4.6.3.6
Rbr850 FirmwareOperating system
Affected:< 3.2.17.12
Rbs850 FirmwareOperating system
Affected:< 3.2.17.12
Rbk852 FirmwareOperating system
Affected:< 3.2.17.12

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. Identify the NETGEAR device model
    Access the router web interface or check the physical device label to confirm the exact model number (CBR40, CBR750, RBR850, RBS850, or RBK852)
    Affected if Device model is NOT one of the five affected models listed - if your model is different, you are not affected by this CVE
  2. Check the installed firmware version
    Access the router web interface (typically at 192.168.1.1) and navigate to Administration > Firmware Update or check the device status page to identify the current firmware version number
    Affected if Firmware version is lower than the patched version for your specific model: CBR40 < 2.5.0.24, CBR750 < 4.6.3.6, or RBR850/RBS850/RBK852 < 3.2.17.12
  3. Verify administrative access status
    Confirm whether the routers web administration interface is accessible and check if administrative accounts exist or are enabled
    Affected if Administrative interface is accessible to untrusted users or uses default credentials, as this vulnerability requires authenticated access to be exploitable
  4. Inspect for suspicious administrative activity
    Review router logs or event history for any unexpected administrative session logins, configuration changes, or commands that were not initiated by authorized administrators
    Affected if Unrecognized administrative sessions, unfamiliar config modifications, or anomalous commands appear in logs, which may indicate successful exploitation

You are affected only if you have a CBR40, CBR750, RBR850, RBS850, or RBK852 device running firmware below the patched version AND the administrative interface is accessible to an attacker.

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 2.5.0.24 / 3.2.17.12 / 4.6.3.6 or later
Fixed in 2.5.0.243.2.17.124.6.3.6
Interim mitigation

Update firmware to the patched versions (CBR40: 2.5.0.24, CBR750: 4.6.3.6, RBK852/RBR850/RBS850: 3.2.17.12). If immediate patching is not possible, limit administrative access to trusted personnel only and monitor for suspicious activity.

Recommended fix High confidence

CBR40: 2.5.0.24 | CBR750: 4.6.3.6 | RBR850/RBS850/RBK852: 3.2.17.12

  1. 1. Identify the exact NETGEAR device model (CBR40, CBR750, RBR850, RBS850, or RBK852)
  2. 2. Access the device's web administration interface
  3. 3. Navigate to the Firmware Update or Administration section
  4. 4. Check the current firmware version under 'Router Info' or similar
  5. 5. Download the appropriate firmware update from NETGEAR's support site (kb.netgear.com)
  6. 6. Upload the firmware file through the web interface and apply the update
  7. 7. Wait for the device to reboot and verify the new firmware version
Caveat Standard firmware update - ensure stable power during upgrade; may reset some configurations to defaults

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

Fix this in Cbr40 Firmware Scoped from the published advisory
  • Consultation3.0 h
  • Implementation2.0 h
  • Testing4.0 h
  • Review / QA2.0 h
11.0 hours of engineering $1,920
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,072.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-45598 — 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-2021-45598 in production — separate from our analysis above.

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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
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  • No spam, self-promotion, credentials, or personal data