CVE-2026-2815
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 · uneditedIncorrect use of the PUF key for user key generation in EFR32xG27 results in predictable keys
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 confidenceThe EFR32xG27 wireless MCU from Silicon Labs incorrectly uses its Physically Unclonable Function (PUF) key during user key generation, resulting in keys that can be predicted rather than being truly random and unique. This stems from improper implementation of PUF-based key derivation in the silicon, allowing attackers to potentially derive the same encryption keys used to protect communications or data.
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
- Adjacent
- Complexity
- Low
- Privileges
- None
- Authentication
- X
- User interaction
- None
- Scope
- X
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
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 EFR32xG27 hardware in your environmentReview device inventory, hardware markings, or use vendor tools (like Silicon Labs Simplicity Studio) to query the chip model via debug interface or firmware identification scriptsAffected if The device is confirmed to be an EFR32xG27 variant
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Check firmware version against vendor advisoriesRetrieve firmware version via debug interface, boot logs, or vendor provisioning tools; compare against any Silicon Labs security advisory for CVE-2026-2815Affected if Firmware version matches the vulnerable release or no patch is listed as applied
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Verify PUF key derivation is in useExamine device configuration, provisioning records, or security settings to determine if PUF-based key generation is enabled; look for PUF-related configuration flags or key derivation method indicators in firmware or provisioning dataAffected if PUF-based key derivation is actively used for user key generation
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Inspect generated keys for predictabilityIf possible, review key generation logs or use vendor diagnostics to verify key uniqueness across multiple devices; check for known patterns or if multiple devices share derived keysAffected if Keys show repetition, predictable patterns, or identical keys across different devices
You are affected if you have deployed EFR32xG27 devices using PUF-based key derivation with unpatched firmware that exhibits predictable or duplicate keys.
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 vendor-supplied firmware update for EFR32xG27 that corrects the PUF key usage, then regenerate all user keys using the corrected implementation and re-provision devices as needed.
- Consultation6.0 h
- Implementation12.0 h
- Testing8.0 h
- Review / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $8,448.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-2815 — 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-2026-2815 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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- 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
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