Video Surveillance 8400 FirmwareOperating system · Cisco
CVE-2021-1521
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 · uneditedA vulnerability in the Cisco Discovery Protocol implementation for Cisco Video Surveillance 8000 Series IP Cameras could allow an unauthenticated, adjacent attacker to cause an affected IP camera to reload. This vulnerability is due to missing checks when processing Cisco Discovery Protocol messages. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol packet to an affected IP camera. A successful exploit could allow the attacker to cause the affected IP camera to reload unexpectedly, resulting in a denial of service (DoS) condition. Note: Cisco Discovery Protocol is a Layer 2 protocol. To exploit this vulnerability, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).
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 vulnerability in the Cisco Discovery Protocol implementation for Cisco Video Surveillance 8000 Series IP Cameras allows an unauthenticated, adjacent attacker on the same Layer 2 broadcast domain to cause the IP camera to reload unexpectedly by sending a malicious CDP packet. The vulnerability is due to missing input validation checks when processing CDP messages.
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
Video Surveillance 8400 FirmwareOperating system
< 1.0.9-11
Video Surveillance 8000p FirmwareOperating system
< 1.0.9-11
Video Surveillance 8020 FirmwareOperating system
< 1.0.9-11
Video Surveillance 8030 FirmwareOperating system
< 1.0.9-11
Video Surveillance 8070 FirmwareOperating system
< 1.0.9-11
Video Surveillance 8620 FirmwareOperating system
< 1.0.9-11
Video Surveillance 8630 FirmwareOperating system
< 1.0.9-11
Video Surveillance 8930 FirmwareOperating system
< 1.0.9-11CVSS 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
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:A/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 IP camera modelAccess the camera's web interface, CLI, or management console and retrieve the exact model number (e.g., Cisco Video Surveillance 8400, 8000p, 8020, 8030, 8070, 8620, 8630, or 8930)Affected if The model is one of the eight affected models listed in the CVE (8400, 8000p, 8020, 8030, 8070, 8620, 8630, 8930)
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Check the firmware versionLog into the camera's web interface or CLI and look for the firmware version information, typically found under System, About, or Device Info sectionsAffected if The installed firmware version is earlier than 1.0.9-11 (e.g., 1.0.9-10, 1.0.8, etc.)
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Verify Cisco Discovery Protocol is enabledAccess the camera's web interface or CLI and check the CDP/Network settings to determine if Cisco Discovery Protocol is enabled on the deviceAffected if CDP is enabled and the device is on a network where untrusted Layer 2 devices can send CDP packets to it
A user is affected if they have one of the eight listed camera models running firmware prior to version 1.0.9-11 with Cisco Discovery Protocol enabled on their network segment.
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 data1.0.9-11
Apply the Cisco firmware patch for CVE-2021-1521. If immediate patching is not possible, consider disabling Cisco Discovery Protocol on affected devices or implementing network segmentation (VLANs/ACLs) to restrict CDP traffic to trusted segments only.
Fix this in Video Surveillance 8400 Firmware
Scoped from the published advisory
- Consultation2.0 h
- Implementation4.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,560.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-1521 — 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-2021-1521 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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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
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