CVE-2023-6640
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 · uneditedMalformed S2 Nonce Get Command Class packets can be sent to crash PC Controller v5.54.0 and earlier.
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 confidenceMalformed S2 Nonce Get Command Class packets can be sent to crash PC Controller v5.54.0 and earlier. This is a denial of service vulnerability in the Z-Wave protocol implementation where specially crafted S2 Nonce Get packets cause the application to crash when processed.
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<= 5.54CVSS 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.
-
Identify the installed PC Controller versionOpen the Silabs Z-Wave PC Controller application and navigate to Help > About, or check the Windows Add/Remove Programs list for the installed version numberAffected if The version listed is 5.54.0 or any version lower than 5.54.0
-
Confirm Z-Wave S2 security is enabledCheck the PC Controller configuration or network settings to see if S2 encrypted Z-Wave devices are included or if S2 security class is activeAffected if S2 Nonce Get packets are only processed when S2 security is enabled in the Z-Wave network
-
Check for application crash eventsReview Windows Event Viewer under Application logs for recent crashes of the PC Controller process, or check for sudden stops in Z-Wave network operation logsAffected if The controller has crashed or become unresponsive after processing Z-Wave traffic, particularly after adding or communicating with S2 encrypted devices
The environment is affected if the installed Silabs Z-Wave PC Controller version is 5.54.0 or earlier and S2 encrypted Z-Wave devices are communicating with the controller, as malformed S2 Nonce Get packets can cause the application to crash.
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 dataUpdate PC Controller software to a version newer than v5.54.0 to receive the vendor patch, or implement network-level filtering of malformed Z-Wave S2 Nonce Get Command Class packets as a compensating control.
- Consultation1.0 h
- Implementation1.0 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 $1,376.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2023-6640 — 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-2023-6640 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
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data