CVE-2023-33221
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 · uneditedWhen reading DesFire keys, the function that reads the card isn't properly checking the boundaries when copying internally the data received. This allows a heap based buffer overflow that could lead to a potential Remote Code Execution on the targeted device. This is especially problematic if you use Default DESFire key.
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 confidenceA heap-based buffer overflow exists in the DesFire key reading function. The vulnerability stems from missing boundary checks when copying card data internally, allowing an attacker to overflow the heap and potentially achieve remote code execution. The risk is elevated when default DESFire keys are in use.
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< 4.15.5< 4.15.5< 4.15.5< 4.15.5< 2.12.2< 2.12.2< 2.12.2< 1.2.7CVSS 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
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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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Check device firmware versionAccess the device admin interface or system settings and locate the firmware version information. For command-line access, use the device's management CLI or API to query the firmware version.Affected if The firmware version is lower than 4.15.5 for Sigma Lite/Lite+/Extreme/Wide, lower than 2.12.2 for Morphowave Compact/Xp/Visionpass, or lower than 1.2.7 for Morphowave Sp.
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Verify DesFire card reader module is enabledCheck the device configuration or admin panel for DesFire/NFC card reader settings. Look for DesFire or NFC card enrollment/read functions in the access control system configuration.Affected if The DesFire card reading functionality is enabled and configured on the device.
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Inspect DESFire key configurationExamine the key management or security settings in the device admin interface. Look for DESFire authentication keys configuration section.Affected if Default factory DESFire keys remain in use rather than unique, cryptographically strong keys having been replaced.
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Check for card data processing activityMonitor the device or review logs for any DesFire card read operations, particularly during enrollment or key provisioning processes.Affected if The device processes DesFire card data with the vulnerable key reading function.
The device is affected if it runs a firmware version below the thresholds AND has DesFire card reading enabled AND uses default DESFire keys, allowing the heap overflow to trigger during card data operations.
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.
dbcve · scoped1.2.72.12.24.15.5
Implement proper length validation before data copy operations and ensure boundary checks validate the incoming data size against the destination buffer. Replace default DESFire keys with unique, cryptographically strong keys.
Sigma devices: firmware 4.15.5 | Morphowave Compact/Xp/Visionpass: firmware 2.12.2 | Morphowave Sp: firmware 1.2.7
- Identify the specific device model (Sigma Lite, Sigma Lite+, Sigma Extreme, Sigma Wide, Morphowave Compact, Morphowave Xp, Visionpass, or Morphowave Sp) and current firmware version
- Download the fixed firmware from the official IDEMIA support portal or authorized distribution channel
- For Sigma devices, upgrade to firmware version 4.15.5 or later
- For Morphowave Compact, Morphowave Xp, and Visionpass devices, upgrade to firmware version 2.12.2 or later
- For Morphowave Sp devices, upgrade to firmware version 1.2.7 or later
- Follow the standard firmware update procedure (typically via device management web interface, USB update, or central management system)
- After upgrade, change the default DESFire keys to custom values if not already done
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation3.0 h
- Implementation6.0 h
- Testing8.0 h
- Review / QA4.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2023-33221 — 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-2023-33221 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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