Contiki NgOperating system

CVE-2023-28116

CRITICAL · 9.8 CVSS v3.1 Published 2023-03-17
Fix available
A fix is available. Upgrade to after 4.8 or later.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click Patch available

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 · unedited
Contiki-NG is an open-source, cross-platform operating system for internet of things (IoT) devices. In versions 4.8 and prior, an out-of-bounds write can occur in the BLE L2CAP module of the Contiki-NG operating system. The network stack of Contiki-NG uses a global buffer (packetbuf) for processing of packets, with the size of PACKETBUF_SIZE. In particular, when using the BLE L2CAP module with the default configuration, the PACKETBUF_SIZE value becomes larger then the actual size of the packetbuf. When large packets are processed by the L2CAP module, a buffer overflow can therefore occur when copying the packet data to the packetbuf. The vulnerability has been patched in the "develop" branch of Contiki-NG, and will be included in release 4.9. The problem can be worked around by applying the patch manually.

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
How this class of weakness works · CWE-120

A fixed-size buffer is filled without checking the length of the incoming data, so it overflows into neighbouring memory. This is the classic overflow attackers use to overwrite return addresses and hijack execution. The fix is strict length checks and safe, bounded string and memory functions.

General guidance for the classic buffer overflow class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →

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
Contiki NgOperating system
Affected:<= 4.8

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
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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 · scoped
Upgrade available Upgrade to a release after 4.8
Vendor patch github.com →
Recommended fix High confidence

Contiki-NG 4.9 or later (or 'develop' branch)

  1. 1. Obtain the fixed version of Contiki-NG by updating to version 4.9 or later, or checkout the 'develop' branch which contains the patch
  2. 2. If using an older version, manually apply the fix from GitHub PR #2398: https://github.com/contiki-ng/contiki-ng/pull/2398
  3. 3. Rebuild the Contiki-NG firmware image for your affected IoT devices
  4. 4. Deploy the updated firmware to all devices running Contiki-NG versions 4.8 and prior that use the BLE L2CAP module
  5. 5. Verify the BLE L2CAP functionality works correctly after the update
Caveat IoT firmware upgrades may introduce compatibility changes with existing applications or peripheral configurations; test thoroughly before production deployment

Generated from the published advisory — verify against the referenced sources before acting.

We can identify the exact fixed release, upgrade, and verify it in staging — typical engagement from $3,550. Get the upgrade done

Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2023-28116 in production — separate from our analysis above.

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What this is

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.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
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