Webex Room Phone FirmwareOperating system · Cisco
CVE-2023-20047
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 Link Layer Discovery Protocol (LLDP) feature of Cisco Webex Room Phone and Cisco Webex Share devices could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient resource allocation. An attacker could exploit this vulnerability by sending crafted LLDP traffic to an affected device. A successful exploit could allow the attacker to exhaust the memory resources of the affected device, resulting in a crash of the LLDP process. If the affected device is configured to support LLDP only, this could cause an interruption to inbound and outbound calling. By default, these devices are configured to support both Cisco Discovery Protocol and LLDP. To recover operational state, the affected device needs a manual restart.
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 resource exhaustion vulnerability in the LLDP (Link Layer Discovery Protocol) implementation on Cisco Webex Room Phone and Webex Share devices allows an adjacent, unauthenticated attacker to send specially crafted LLDP packets that exhaust memory resources, causing the LLDP process to crash and requiring manual device restart to recover.
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
Webex Room Phone FirmwareOperating system
<= 1.2.0
Webex Share FirmwareOperating system
<= 1.2.0
Sip Ip Phone SoftwareApplication
<= 1.2.0CVSS 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 device modelLocate the physical device or check network inventory to determine if the device is a Cisco Webex Room Phone, Cisco Webex Share, or Cisco Sip Ip Phone.Affected if Device is any of these three models
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Check firmware versionAccess the device admin interface or web console and navigate to the version or status page to retrieve the current firmware version. Compare this version against the affected range <= 1.2.0.Affected if Firmware version is 1.2.0 or earlier
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Verify LLDP is enabledAccess the device network settings through the admin interface or web console. Look for LLDP (Link Layer Discovery Protocol) settings and confirm whether it is turned on or enabled.Affected if LLDP is enabled and running on the device
Device is affected if it is a Cisco Webex Room Phone, Webex Share, or Sip Ip Phone running firmware version 1.2.0 or earlier AND has LLDP enabled.
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 the vendor patch when available. As a workaround, disable LLDP on affected devices if business requirements allow, as the vulnerability only affects LLDP and not Cisco Discovery Protocol.
Fix this in Webex Room Phone Firmware
Scoped from the published advisory
- Consultation4.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,600.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2023-20047 — 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-2023-20047 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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