CVE-2021-45503
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 · uneditedCertain NETGEAR devices are affected by authentication bypass. This affects CBR750 before 4.6.3.6, RBK752 before 3.2.17.12, RBR750 before 3.2.17.12, RBS750 before 3.2.17.12, 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 · moderate confidenceNETGEAR Orbi mesh WiFi systems (RBK752, RBR750, RBS750, RBK852, RBR850, RBS850) and CBR750 cable router contain an authentication bypass vulnerability allowing unauthorized access to the device management interface. The vulnerability affects specific firmware versions before 3.2.17.12 (Orbi) and 4.6.3.6 (CBR750). The CVSS 8.8 score indicates network-exploitable authentication bypass with low privilege requirements.
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< 4.6.3.6< 3.2.17.12< 3.2.17.12< 3.2.17.12< 3.2.17.12< 3.2.17.12< 3.2.17.12CVSS 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
- Adjacent
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:A/AC:L/PR:N/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 checksWork through these to decide whether this CVE applies to you.
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Identify the NETGEAR device modelLocate the device label on the router or satellite unit, or log into the web management interface and look for the model number (RBK752, RBR750, RBS750, RBK852, RBR850, RBS850, or CBR750)Affected if The device is any of the listed affected models (RBK752, RBR750, RBS750, RBK852, RBR850, RBS850, CBR750)
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Check the installed firmware versionLog into the web management interface and navigate to the Administration > Firmware Update or Settings page to view the current firmware version, or use the NETGEAR Orbi app which displays the firmware version under device settingsAffected if The firmware version cannot be determined or is not visible in the management interface
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Compare Orbi firmware version to the fixed releaseIf the device is an Orbi system (RBK752, RBR750, RBS750, RBK852, RBR850, or RBS850), compare the installed firmware version against 3.2.17.12Affected if The firmware version is lower than 3.2.17.12 (for Orbi devices)
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Compare CBR750 firmware version to the fixed releaseIf the device is a CBR750 cable router, compare the installed firmware version against 4.6.3.6Affected if The firmware version is lower than 4.6.3.6 (for CBR750 devices)
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Verify web management interface accessibilityAttempt to access the device web interface from the network by navigating to the router IP address (commonly 192.168.1.1) or check if remote management is enabled under Administration > Remote ManagementAffected if The web management interface is accessible from the network (this is required for exploitation)
The device is affected if it is one of the listed models (RBK752, RBR750, RBS750, RBK852, RBR850, RBS850, or CBR750) and the firmware version is below 3.2.17.12 for Orbi devices or below 4.6.3.6 for CBR750, with the management interface exposed to the network.
Generated from the published advisory. Verify against your own configuration.
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 · scoped3.2.17.124.6.3.6
Update NETGEAR device firmware to version 3.2.17.12 or later for Orbi systems (RBK752/RBR750/RBS750/RBK852/RBR850/RBS850) and 4.6.3.6 or later for CBR750. If updating is not immediately possible, restrict administrative access to the device's web interface by isolating it on a trusted VLAN or disabling remote management.
CBR750: firmware version 4.6.3.6 or later; RBK752/RBR750/RBS750/RBK852/RBR850/RBS850: firmware version 3.2.17.12 or later
- Identify your specific NETGEAR device model from the affected list (CBR750, RBK752, RBR750, RBS750, RBK852, RBR850, or RBS850)
- Navigate to the NETGEAR support website (kb.netgear.com) or download center and locate the firmware download page for your device model
- Download the latest firmware version: CBR750 requires version 4.6.3.6 or later; all other affected models require version 3.2.17.12 or later
- Access your router's web-based management interface by entering the router's IP address in a web browser
- Log in with administrator credentials
- Navigate to the Advanced tab > Administration > Firmware Update (or similar path depending on model)
- Click Check for New Version or use the manual upload option to select the downloaded firmware file
- Wait for the firmware to upload, install, and the router to reboot - do not power off the device during this process
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation3.0 h
- Testing2.0 h
- Review / QA1.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2021-45503 — 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 sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-45503 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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