Wcn3988 FirmwareOperating system · Qualcomm

CVE-2026-21375

HIGH · 7.8 CVSS v3.1 Published 2026-04-06
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
80/100
Remediation priority · High
Zero-click

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
Memory Corruption when accessing an output buffer without validating its size during IOCTL processing.

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 confidence

Memory corruption vulnerability exists due to missing size validation when accessing an output buffer during IOCTL (I/O Control) request processing. An attacker can potentially trigger the vulnerability by sending specially crafted IOCTL requests with insufficient output buffer sizes, leading to memory corruption and possible privilege escalation.

MitigationImplement proper buffer size validation in all IOCTL handlers before accessing output buffers; ensure the provided buffer size meets minimum requirements and does not exceed allocated buffer space.

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
Wcn3988 FirmwareOperating system
Affected:all versions
Wsa8830 FirmwareOperating system
Affected:all versions
Wsa8832 FirmwareOperating system
Affected:all versions
Wsa8835 FirmwareOperating system
Affected:all versions
Wsa8840 FirmwareOperating system
Affected:all versions
Wsa8845 FirmwareOperating system
Affected:all versions
Wsa8845h FirmwareOperating system
Affected:all versions
X2000077 FirmwareOperating system
Affected:all versions

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
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 checks

Work through these to decide whether this CVE applies to you.

  1. Identify Qualcomm chip model
    Check system information, kernel logs, or device firmware metadata to determine the exact Qualcomm chip model (e.g., Wcn3988, Wsa8830, Wsa8832, Wsa8835, Wsa8840, Wsa8845, Wsa8845h, or X2000077)
    Affected if The chip model matches any of the affected products: Wcn3988, Wsa8830, Wsa8832, Wsa8835, Wsa8840, Wsa8845, Wsa8845h, or X2000077
  2. Determine firmware version
    Read the firmware version string from the device (via dmesg, /sys/firmware, or vendor diagnostic tools) and compare against 'all versions' - note that the vendor lists all versions as affected
    Affected if Any firmware version is present on the identified affected chip model
  3. Verify IOCTL interface is exposed
    Check if the device exposes IOCTL interfaces for the wireless/audio subsystem (look for /dev/wcn* or similar device nodes, or check driver configuration for IOCTL support)
    Affected if IOCTL interfaces are accessible and the affected firmware is in use
  4. Check for vendor-specific IOCTL handlers
    Inspect the driver or firmware configuration to confirm IOCTL handlers exist for the Qualcomm chip (this is typically built into the firmware)
    Affected if IOCTL handlers are present in the firmware for the affected chip model

If your device uses any Qualcomm firmware variant among Wcn3988, Wsa8830, Wsa8832, Wsa8835, Wsa8840, Wsa8845, Wsa8845h, or X2000077 with IOCTL functionality enabled, the environment is affected since all versions of these firmwares lack proper buffer size validation.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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 data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Implement proper buffer size validation in all IOCTL handlers before accessing output buffers; ensure the provided buffer size meets minimum requirements and does not exceed allocated buffer space.

Fix this in Wcn3988 Firmware Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing12.0 h
  • Review / QA4.0 h
28.0 hours of engineering $4,760
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-21375 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-21375 in production — separate from our analysis above.

No notes yet

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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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