[CVE-2026-93825][LOW] spi: Add NULL check for spi_get_device_id() in spi_get_device_match_data() [ Upstream

[CVE-2026-93825][LOW] spi: Add NULL check for spi_get_device_id() in spi_get_device_match_data() [ Upstream

[AL-KERNEL]

CVE: CVE-2026-93825
Priority: LOW
AL-KERNEL base severity: LOW
KPANIC flag: NO
Patch: spi: Add NULL check for spi_get_device_id() in spi_get_device_match_data() [ Upstream
Commit: 3fcd9415144f4fbd21e1bef35a7f8dbd734f607d
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=3fcd9415144f4fbd21e1bef35a7f8dbd734f607d
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-93825
Analysis date: Thu, 24 Sep 2026 13:44:14 -0400
ActionableScore: 0
ActionableScore lower bound: unknown
Actionable bucket: Ordinary Moderate
Manual review required: NO

Summary:
No one-sentence report phrase was found.

======================================================================
ABOUT THIS REPORT
======================================================================

The original Linux kernel CVE announcement for CVE-2026-93825 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-93825

The original announcement does not normally provide a security severity
estimate, CVSS assessment, or enough information to determine whether the
reported kernel bug represents a practically relevant security issue.

This report was generated by AL-KERNEL, an AI-assisted Linux kernel
vulnerability analysis system developed by Alexander Larkin. It combines
an autonomous classifier with LLM-assisted technical analysis and a
separate ActionableScore mechanism.

The purpose of this report is to prioritize Linux kernel CVEs before
manual review, identify cases that require prompt investigation, and
support automatic closure of issues that are unlikely to have meaningful
security impact.

Published priority for this report: LOW
Manual review required: NO

A detailed explanation of the methodology and priority rules is included
at the end of this message.

======================================================================
AL-KERNEL CLASSIFICATION RESULT
======================================================================

CVE-2026-93825	LOW	https://www.kernelcve.org/list/?q=CVE-2026-93825 CHECK WITH IMPACT FROM ORIG NN MODERATE	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H';**CWE-476;CWE-754;*CWE-20;BEST CVSS score: '4.4';DESCR 'A NULL pointer dereference can occur in spi_get_device_match_data when spi_get_device_id returns NULL and the code accesses the missing SPI ID entry driver_data field. This can happen when driver_override binds a driver to an SPI device without a matching SPI ID table entry, causing a kernel oops or panic. For the CVSS the PR:H because reliable triggering normally requires administrative control over sysfs driver binding or driver_override configuration. The issue is local and not network reachable. Impact is denial of service only. The patch context does not show a use after free out of bounds access information leak or write primitive.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 0)	YES	NULLPTR SIMPLEFIX HARDWARE  DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3	NO	NO	checked

======================================================================
ACTIONABLESCORE ANALYSIS
======================================================================

ActionableScore=0
PrimitiveClass=CLASS_C
RealUAF=NO
HostAdminRequired=YES
NamespaceScopedPrivilege=NO
ImportantCandidate=NO
ManualReview=NO
AutoDowngradeAllowed=YES

1. ActionableScore

* Raw conservative score: -1
* Conservative score: 0
* Raw paranoid score: -1
* Paranoid score: 0
* Conservative normalization: -1 -> 0 because ActionableScore is not negative.
* Paranoid normalization: -1 -> 0 because ActionableScore is not negative.
* Final recommended bucket: **Ordinary Moderate**::

2. Signal breakdown

* +1 Reliable kernel crash or strong DoS. Dereferencing the NULL result of spi_get_device_id in spi_get_device_match_data can cause a kernel Oops or panic.
* -2 Full host-admin-equivalent privilege. Reliable triggering requires writing driver_override and binding or reprobeing a driver through host sysfs device management interfaces. These operations are normally restricted to a host administrator.
* No UAF or stale post-lifetime object use is established.
* No OOB read or write is established.
* No arbitrary or directed write is established.
* No controlled reclaim or object replacement is established.
* No confidentiality or integrity signal is awarded. The bug is a direct NULL pointer dereference before an attacker-controlled structured object is consumed.
* No remote reachability is established. SPI driver binding is a local host control-plane operation.
* No extra Availability point is awarded because the potential Oops or panic is already counted as the Reliable kernel crash signal.
* No local unprivileged trigger is awarded because the complete driver_override and driver-binding sequence requires privileged host device administration.
* No race or timing penalty applies. The described trigger is an ordered configuration state, not a timing race.

3. Reachability analysis

The trigger requires a local actor able to configure driver_override for an SPI device and cause the relevant driver binding path to execute without a matching SPI device ID entry.

The relevant operations are host sysfs device-management operations. They normally require host-administrator-equivalent authority, such as root or equivalent privileges over host device management. This is not an ordinary-user SPI data-plane interface.

No namespace-scoped complete trigger chain is established. A network namespace, user namespace, or container does not normally provide authority to rebind host SPI devices or modify host SPI driver_override attributes. No prior special hardware condition beyond the presence of an SPI device and affected driver is required, but the attacker must already have host administrative device-control access.

4. Primitive and severity interpretation

The exact primitive is a NULL pointer dereference. spi_get_device_id can return NULL when driver_override selects a driver without a matching SPI ID table entry, and the old code immediately dereferences the returned pointer to access driver_data.

This is not a UAF, double free, refcount corruption, OOB access, type confusion, or authorization bypass. There is no active structured stale object, no post-free reuse, and no attacker-controlled replacement object. The demonstrated consequence is a local kernel Oops or panic causing denial of service.

PrimitiveClass is CLASS_C because the behavior is crash and invalid-state handling without an independently useful kernel-corruption primitive. ImportantCandidate is NO because the patch establishes only a NULL dereference in a privileged local device-management path. AutoDowngradeAllowed is YES because no unresolved lifetime, ownership, memory-corruption, or security-boundary primitive remains.

Likely operational severity is low. An actor able to administer host SPI driver binding already has substantial control over the host and can generally cause broader disruption by other means.

5. One-sentence report phrase

A privileged local user can trigger a kernel NULL pointer dereference by binding an SPI driver through driver_override without a matching SPI ID entry, causing a local denial of service.

6. Manual review recommendation

NO MANUAL CHECK NEEDED

The patch demonstrates a privileged local NULL dereference only, with no memory-corruption, lifetime, disclosure, integrity, or security-boundary primitive.

7. Call-site confidence

Call-site confidence: medium

======================================================================
UPSTREAM PATCH SUMMARY
======================================================================

Patch: spi: Add NULL check for spi_get_device_id() in spi_get_device_match_data() [ Upstream
Commit: 3fcd9415144f4fbd21e1bef35a7f8dbd734f607d
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=3fcd9415144f4fbd21e1bef35a7f8dbd734f607d

Changed files:
  drivers/spi/spi.c

Diff excerpt:

Not included in this email. See the upstream URL for the full patch.

Full patch:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=3fcd9415144f4fbd21e1bef35a7f8dbd734f607d

======================================================================
DETAILED REPORT METHODOLOGY
======================================================================

The original Linux kernel CVE announcement for CVE-2026-93825 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-93825

The original CVE announcement normally does not include a security-level
estimate. In particular, it may not contain a CVSS assessment, an impact
level, or enough information to determine whether the reported bug is a
practically relevant security issue. One purpose of this parallel CVE list
is to provide that missing technical and prioritization information.

The original goal of the AL-KERNEL project was to prioritize Linux kernel
CVE analysis automatically before manual review. The system can also help
identify non-security issues that may be suitable for automatic closure.

This report was generated by AL-KERNEL, an AI-assisted Linux kernel
vulnerability analysis system developed by Alexander Larkin.

The first analysis stage combines an autonomous classifier with additional
LLM-based analysis. The autonomous classifier runs locally on a CPU and is
based on a backpropagation neural network. Together, these mechanisms
produce a technical vulnerability description, identify likely weakness
types, estimate CVSS severity, and provide input for ActionableScore.

Two CVSS estimates are retained because incomplete kernel vulnerability
information often permits more than one defensible interpretation:

  Conservative CVSS vector: Not available
  The Best / paranoid CVSS vector: AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
  The Best / paranoid CVSS score: 4.4

The conservative vector represents a lower-impact interpretation.
The Best/paranoid vector intentionally represents a plausible upper-bound
interpretation and should not automatically be treated as demonstrated
real-world impact.

CVSS may also need to be adjusted for a particular Linux deployment,
because actual reachability, privileges, enabled kernel configuration,
hardware, namespaces, exposed device nodes, and other environmental
conditions can differ significantly between systems.

A separate ActionableScore mechanism evaluates practical remediation
urgency. Its analysis may include reachability, attack prerequisites,
subsystem exposure, memory-corruption characteristics, denial-of-service
reliability, and possible confidentiality, integrity, or
privilege-escalation impact.

  Conservative ActionableScore: unknown
  Paranoid ActionableScore: 0

The final base severity is taken directly from the second tab-separated
field of the AL-KERNEL classification result. ActionableScore does not
replace or independently override that final AL-KERNEL decision, and
if ActionableScore adjusted impact level of ALKERNEL, then you would see
self-readable flags above like INCREASED_TO_HIGH_BASED_ON_ACTIONABLESCOREHIGHEREQTHAN7.

For an AL-KERNEL result of MODERATE, this report uses the following
additional presentation split:

  ActionableScore below 5   -> MODERATE REGULAR
  ActionableScore 5 or more -> MODERATE 7.0

The distinction between MODERATE REGULAR and MODERATE 7.0 makes it
possible to identify Moderate issues that should receive manual analysis
and fixes before lower-priority MODERATE REGULAR issues. In many cases,
MODERATE REGULAR fixes may wait for a later rebase or routine update.

There is one override in which MODERATE REGULAR becomes MODERATE 7.0
even when the ActionableScore is below 5. When the AL-KERNEL result
contains the KPANIC flag, a MODERATE result is always presented as
MODERATE 7.0. The KPANIC flag selected with few regexps without
usage of AI at all, so it helps to detect cases when Kernel Crash happens
and similar (to filter False-Negative results from the LLM usage).

KPANIC indicates that a reliable kernel crash, kernel panic, or similarly
serious kernel availability impact was identified by the classification
workflow.

AL-KERNEL base severity for this report: LOW
KPANIC detected for this report: NO
Published priority for this report (same as in Subject): LOW

These results are intended to support engineering triage. They are
machine-generated estimates, and cases marked for manual review should
be validated by a human security engineer before final disposition.
For more info read docs linked from here: https://kernelcve.org/
(and you can submit you own patch there to generate such a report
for non-existant CVE-id yet).

Note that in many cases this AI tool selects higher severity, than
real is (means you can expect Importants instead of Moderate 7.0 or
Moderates 7.0 instead of regular Moderates). If you see such cases,
please use reply email interface to add additional manual analyses
info to this particular CVE.
And please, please, let me know when you see Lows instead of Importants
or Important instead of Low (because particular for such cases I
need to tune this AI tool to make it better for this one and next similar).
My contact email for such notifications is alexanjelausa@gmail.com (and both
send reply to CVE record itself too and see "reply" button below for howto reply).