CVE-2024-12378
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 · uneditedOn affected platforms running Arista EOS with secure Vxlan configured, restarting the Tunnelsec agent will result in packets being sent over the secure Vxlan tunnels in the clear.
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 confidenceOn Arista EOS platforms with secure Vxlan configured, restarting the Tunnelsec agent causes a failure in the encryption handling, resulting in packets being transmitted over secure Vxlan tunnels without encryption. This creates a critical data confidentiality breach where encrypted tunnels appear operational but traffic flows in plaintext.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
CVSS 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
- High
- Integrity
- High
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
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 platform and EOS versionRun 'show version' or 'show hardware' to confirm the device is Arista EOS and note the EOS version number for comparison against any affected version rangesAffected if Device is not running Arista EOS or version is outside affected ranges
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Check if secure Vxlan is configuredRun 'show vxlan interface' and look for secure Vxlan configuration entries, or run 'show running-config | include vxlan' to view Vxlan configurationAffected if Secure Vxlan is not configured on this device
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Verify Tunnelsec agent statusRun 'show process | include tunnelsec' or 'systemctl status tunnelsec' (depending on EOS version) to confirm the Tunnelsec agent is currently runningAffected if Tunnelsec agent is not running
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Check for recent Tunnelsec agent restartsRun 'show log | include tunnelsec' or check system logs for recent Tunnelsec process restarts or failures within the past hoursAffected if Tunnelsec agent has not been restarted recently
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Verify encryption is actively applied to Vxlan trafficRun 'show vxlan encryption status' or 'show secure vxlan status' to confirm encryption is operational, and use packet capture on the Vxlan tunnel interface to verify outbound traffic is actually encryptedAffected if Encryption shows as enabled in config but traffic analysis reveals plaintext packets on the secure tunnel
The environment is affected if running Arista EOS with secure Vxlan configured AND the Tunnelsec agent has been restarted since the last reboot, with plaintext traffic detected on what should be an encrypted tunnel.
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 available Arista EOS patches for this vulnerability. Until patched, avoid unnecessary Tunnelsec agent restarts and implement additional network monitoring to detect unencrypted traffic on what should be secure Vxlan tunnels.
- Consultation4.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA2.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2024-12378 — 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-2024-12378 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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