CVE-2021-33137
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 · uneditedOut-of-bounds write in the Intel(R) Kernelflinger project may allow an authenticated user to potentially enable escalation of privilege via local access.
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 confidenceThis is an out-of-bounds write vulnerability in Intel Kernelflinger, which is Intel's bootloader/firmware component used in Android devices. The vulnerability allows an authenticated local user to write data beyond allocated memory boundaries, potentially corrupting memory and enabling privilege escalation from a lower-privileged account to higher system privileges.
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< 2021-06-28CVSS 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
- Local
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:L/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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Identify if device uses Intel KernelflingerCheck if the Android device uses an Intel SoC (System-on-Chip) and review device manufacturer documentation or system information for the presence of Intel Kernelflinger bootloader. Intel Kernelflinger is used primarily on Intel-based Android devices.Affected if Device runs Intel-based Android firmware with Kernelflinger as the bootloader
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Determine Kernelflinger firmware versionLocate the Kernelflinger version information in the device firmware. This may be available through manufacturer-specific tools, firmware metadata, or by checking bootloader version strings if accessible. The version is date-based (the fix was released on 2021-06-28).Affected if Version date is before 2021-06-28
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Check bootloader/firmware build dateIf the version cannot be directly determined, check the build date of the bootloader or overall firmware image through device diagnostics, manufacturer update tools, or system properties that expose build timestamps.Affected if Build date of bootloader/firmware is earlier than June 28, 2021
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Verify Intel processor-based Android deviceConfirm the device contains an Intel processor/APU. This can be checked via CPU information in /proc/cpuinfo on rooted devices, or through the device specification sheet from the manufacturer.Affected if Device uses Intel hardware but cannot confirm Kernelflinger was patched to 2021-06-28 or later
User is affected if the device runs Intel Kernelflinger bootloader with a version or build date earlier than 2021-06-28.
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 · scoped2021-06-28
Apply Intel's firmware/security updates for Kernelflinger once released. Since this is a firmware-level vulnerability in the bootloader, organizations should ensure devices are enrolled in Intel's update programs and verify that firmware is patched to the latest validated version.
Kernelflinger version 2021-06-28 or later
- Identify the current version of Intel Kernelflinger in use
- Obtain the fixed version of Kernelflinger (2021-06-28 or later) from Intel's official sources
- Follow Intel's standard upgrade procedure for Kernelflinger
- Verify the upgrade was successful and the version is now >= 2021-06-28
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation6.0 h
- Implementation12.0 h
- Testing10.0 h
- Review / QA5.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $9,216.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-33137 — 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-2021-33137 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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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