CVE-2021-45992
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 · uneditedTenda routers G1 and G3 v15.11.0.17(9502)_CN were discovered to contain a stack overflow in the function formSetQvlanList. This vulnerability allows attackers to cause a Denial of Service (DoS) via the qvlanName parameter.
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 confidenceA stack-based buffer overflow vulnerability exists in the formSetQvlanList function of Tenda G1 and G3 routers running firmware version 15.11.0.17(9502)_CN. The vulnerability is triggered via the qvlanName parameter, allowing an attacker to overflow the stack buffer and cause a denial of service.
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= 15.11.0.17\(9502\)_cn= 15.11.0.17\(9502\)_cnCVSS 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 checksWork through these to decide whether this CVE applies to you.
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Identify the Tenda router modelAccess the router web interface or check the device label to confirm the model is G1 or G3Affected if The router is a Tenda G1 or G3 device
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Check the installed firmware versionLog into the router web interface and navigate to System Settings > Firmware Upgrade, or use the router's admin panel to view system information. The firmware version is typically displayed as '15.11.0.17(9502)_CN'Affected if The firmware version is exactly 15.11.0.17(9502)_CN
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Verify qvlan functionality is accessibleCheck the router web interface for qvlan or VLAN configuration pages. The vulnerability exists in the formSetQvlanList function which handles qvlanName parameter requestsAffected if The qvlan configuration feature is enabled and accessible through the router's web interface
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Confirm the formSetQvlanList endpoint existsAttempt to access or inspect the router's HTTP handlers. The vulnerable function formSetQvlanList processes the qvlanName parameter without proper bounds checkingAffected if The router exposes a web endpoint that calls formSetQvlanList and accepts the qvlanName parameter
You are affected if you have a Tenda G1 or G3 router running firmware version 15.11.0.17(9502)_CN with the qvlan feature enabled and accessible.
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.
From vendor dataApply vendor-supplied firmware updates when available; if no update exists, consider network segmentation or disabling the affected qvlan functionality to reduce exposure.
- Consultation4.0 h
- Implementation2.0 h
- Testing3.0 h
- Review / QA2.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2021-45992 — 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-2021-45992 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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