Ios XeOperating system · Cisco
CVE-2020-3512
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 PROFINET handler for Link Layer Discovery Protocol (LLDP) messages of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to cause a crash on an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient validation of LLDP messages in the PROFINET LLDP message handler. An attacker could exploit this vulnerability by sending a malicious LLDP message to an affected device. A successful exploit could allow the attacker to cause the affected device to reload.
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 PROFINET handler for Link Layer Discovery Protocol (LLDP) messages in Cisco IOS Software and Cisco IOS XE Software allows an unauthenticated, adjacent attacker to cause a device reload by sending a malicious LLDP message. The root cause is insufficient validation of LLDP messages in the PROFINET LLDP message handler.
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
Ios XeOperating system
= 15.2\(7\)eCVSS 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
- Changed
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/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 software versionExecute 'show version' and locate the IOS or IOS XE version string (for example, 15.2(7)E or similar)Affected if The installed version matches 15.2(7)e exactly (note: this appears to be a specific point version, not a range)
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Confirm the product is IOS XEVerify the output of 'show version' indicates Cisco IOS XE Software rather than classic IOSAffected if The device runs IOS XE and the version matches the affected version string
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Verify PROFINET is enabledExecute 'show running-config | include profinet' or 'show profinet status' to check if the PROFINET feature is configuredAffected if PROFINET is enabled and running on the device (the vulnerability only affects the PROFINET LLDP handler)
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Check LLDP configurationExecute 'show lldp neighbors' or 'show running-config | include lldp' to confirm LLDP is enabledAffected if LLDP is globally enabled (LLDP must be running for the PROFINET LLDP handler to be reachable)
You are affected if the device runs IOS XE version 15.2(7)e, has PROFINET enabled, and has LLDP running - the attacker only needs adjacent network access to send the malicious LLDP packet that triggers the reload.
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 relevant Cisco security update for IOS/IOS XE. As an interim measure, consider disabling PROFINET or segmenting the network to limit adjacent attack surface until the patch can be deployed.
Fix this in Ios Xe
Scoped from the published advisory
- Consultation3.0 h
- Implementation3.0 h
- Testing3.0 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 $3,120.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-3512 — 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-2020-3512 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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