CVE-2026-21372
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 · uneditedMemory Corruption when sending IOCTL requests with invalid buffer sizes during memcpy operations.
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 memory corruption vulnerability exists in IOCTL request handling where invalid buffer sizes are not properly validated before memcpy operations. Attackers sending specially crafted IOCTL requests with mismatched buffer sizes can trigger heap or stack corruption, potentially leading to arbitrary code execution or denial of service.
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 dataall versionsall versionsall versionsall versionsall versionsall versionsall versionsall versionsCVSS 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 installed Qualcomm firmware versionCheck the system firmware or baseband firmware version using commands like 'at+ver', 'at+qmss', or by reading /proc/version on embedded systems. For mobile devices, check Settings > About Phone > Baseband version.Affected if The firmware version matches any of: X2000094, Xg101002, Xg101032, Xg101039, X2000092, X2000090, X2000086, or X2000077
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Confirm device uses affected Qualcomm chipsetIdentify the chipset model via 'lspci' for PCIe, 'lsusb' for USB devices, or check hardware documentation. Qualcomm X200 and Xg101 series chipsets are associated with the affected firmware.Affected if The chipset is identified as part of the Qualcomm X200 or Xg101 product line families receiving the listed firmware versions
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Verify IOCTL interface exposureCheck if the device exposes IOCTL interfaces by examining /dev entries, searching for ioctl syscall usage in application binaries, or reviewing kernel module exports with 'cat /proc/kallsyms | grep ioctl' or similar debugging interfaces.Affected if IOCTL interfaces are accessible to untrusted inputs, creating an attack vector for the vulnerability
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Inspect IOCTL handler implementationReverse engineer or inspect the firmware image for IOCTL handler code that performs memcpy operations without proper size validation. Look for patterns where user-provided size parameters are used directly in memory copy functions.Affected if IOCTL handlers perform memcpy using size parameters from requests without validating they match expected buffer dimensions
The environment is affected if the installed Qualcomm firmware version corresponds to any of the X2000094, Xg101002, Xg101032, Xg101039, X2000092, X2000090, X2000086, or X2000077 firmware builds, since all versions of these products contain the unvalidated memcpy flaw in their IOCTL handling.
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 dataImplement strict buffer size validation in all IOCTL handlers, verifying that user-provided size parameters match the expected buffer sizes before performing memcpy operations.
- Consultation6.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA4.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-21372 — 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-2026-21372 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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