[CVE-2026-98658][MODERATE REGULAR] iio: proximity: aw96103: validate firmware data length

[AL-KERNEL <alkernel@kernelcve.org>]

CVE: CVE-2026-98658
Priority: MODERATE REGULAR
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: iio: proximity: aw96103: validate firmware data length
Commit: 4a9b9f2d4e26589afd0ac099c8e5593170dd5ac7
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=4a9b9f2d4e26589afd0ac099c8e5593170dd5ac7
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98658
Analysis date: Sat, 24 Oct 2026 03:55:06 -0400
ActionableScore: 0
ActionableScore lower bound: unknown
Actionable bucket: Ordinary Moderate
Manual review required: NO

Summary:
Malformed AW96103 firmware can drive repeated heap OOB reads and a plausible kernel fault, without a demonstrated disclosure or kernel-memory write.

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

The original Linux kernel CVE announcement for CVE-2026-98658 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98658

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: MODERATE REGULAR
Manual review required: NO

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

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AL-KERNEL CLASSIFICATION RESULT
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CVE-2026-98658	MODERATE	https://www.kernelcve.org/list/?q=CVE-2026-98658 CHECK WITH IMPACT FROM ORIG NN MODERATE | AEGIS IMPACT MODERATE_KPANIC AEGIS_AS=1 LEGACY=MODERATE RESULT=DIFF (final Legacy and Aegis differ; FINAL: MODERATE, Aegis: MODERATE_KPANIC)	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:H';CWE-125;CWE-191;*CWE-20;Other CVSS 'AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '5.6';DESCR 'The AW96103 firmware parser trusted a little endian length from the binary header and used it to process six byte register and value entries without proving that the payload remained inside the copied firmware buffer. A value below the four byte count size underflows into a very large length, while a truncated or inconsistent image can cause repeated out of bounds reads and potentially a kernel fault. The demonstrated primitive is an out of bounds read rather than an out of bounds write or UAF. Adjacent heap data may also be interpreted as device register data, but direct information disclosure or kernel memory modification is not established. For the CVSS the PR:H value is used because reliable triggering normally requires installing or replacing the device firmware file, which generally requires administrative control. The issue is local and is not directly network reachable. Automated impact decision path. The original SimpleNet classifier selected MODERATE_KPANIC. The primary LLM estimated paranoid CVSS 5.6 and the production ActionableScore returned 0 with recommendation Ordinary Moderate. The production rules then evaluated CVSS thresholds and ActionableScore thresholds. Recorded rule transitions were ActionableScore thresholds stage MODERATE_KPANIC to MODERATE because the ActionableScore threshold rule was applied. The legacy KP specialist has no review artifact for this run. The legacy FD or DH downgrade specialist has no review artifact for this run. Exact triggered rule markers were DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN4 and V41_INHERITED_KPANIC_PROMOTION_BLOCKED and MANUAL_REVIEW_REQUIRED. The independent weaker Aegis shadow evaluated CVSS 2.3 and ActionableScore 1 with primitive class CLASS_C and manual review REQUIRED. Its independently reconciled impact was MODERATE_KPANIC. The models disagreed but the aggregation rules retained the production result. The final reported impact is MODERATE.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 0)	MAYBE	OOB LINUS  DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN4 V41_INHERITED_KPANIC_PROMOTION_BLOCKED MANUAL_REVIEW_REQUIRED	-	-	checked

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

ActionableScore=0
PrimitiveClass=CLASS_C
RealUAF=NO
HostAdminRequired=UNKNOWN
NamespaceScopedPrivilege=NO
ImportantCandidate=NO
ManualReview=RECOMMENDED
AutoDowngradeAllowed=YES
RequiresHostUID0=UNKNOWN
AuthorizationDecisionBypass=NO
ProtectedResourceImpact=NONE
B4PendingReview=NO
B4PendingConfirmed=NO

1. ActionableScore

* Raw base score: 0.
* Conservative score: 0; no floor or cap applied.
* Raw paranoid score: 0.
* Paranoid score: 0; no separate defensible stronger primitive.
* Final recommended bucket: **Ordinary Moderate**::

2. Signal breakdown

* +1 limited heap out-of-bounds read: unchecked `valid_data_len` lets the six-byte parser read beyond `aw_bin->data`.
* +1 plausible kernel crash: underflow can create a very large loop bound and eventually access invalid memory.
* -2 uncommon hardware-specific path: execution is tied to an AW96103/AW96105 proximity-sensor driver and its firmware-loading path.
* No confidentiality point: adjacent heap bytes are interpreted internally as register/value data, but no read-back or disclosure path is shown.
* No integrity point: subsequent device register writes may use unintended values, but no protected kernel state or cross-authority data is shown modified.
* NEW52/B5-R does not apply: there is no confirmed heap OOB write, retry-accumulated index, or corrupted kernel state consumer.
* No UAF, controlled reclaim, arbitrary write, authorization bypass, or extra availability effect is shown.

3. Reachability analysis

Triggering requires supplying a malformed device firmware image to the driver. The evidence says this generally requires administrative control, but does not establish the exact firmware provisioning interface or prove host-admin-only triggering; therefore `HostAdminRequired=UNKNOWN` and `RequiresHostUID0=UNKNOWN`. No namespace-scoped operation, remote path, race, or retry sequence is present. Compatible physical hardware is materially required.

4. Primitive and severity reading

The exact primitive is a heap-buffer OOB read caused by unchecked truncation, subtraction underflow, and failure to require complete six-byte entries. Read values can reach device-register operations, but the patch does not show a kernel-memory write, disclosure, protected-resource modification, or host-wide effect beyond a plausible fault. This is CLASS_C rather than B5-R or an Important-preserving corruption primitive. Auto-downgrade remains allowed because the demonstrated behavior is constrained and no material unknown cross-boundary primitive remains.

5. One-sentence report phrase

Malformed AW96103 firmware can drive repeated heap OOB reads and a plausible kernel fault, without a demonstrated disclosure or kernel-memory write.

6. Manual review advice

MANUAL CHECK RECOMMENDED

Confirm the actual firmware-supply permissions and whether unintended device-register programming can cause effects beyond a device-local malfunction.

7. Call-site confidence

Call-site confidence: high

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

Patch: iio: proximity: aw96103: validate firmware data length
Commit: 4a9b9f2d4e26589afd0ac099c8e5593170dd5ac7
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=4a9b9f2d4e26589afd0ac099c8e5593170dd5ac7

Commit description:

The firmware parser reads a length from the binary header and then uses
it to walk six-byte register/value entries. A truncated firmware image
can make the parser read beyond the copied firmware buffer. A value
smaller than the four-byte count field also underflows, producing a very
large length.

Read the little-endian field with get_unaligned_le32(), as previously
proposed by David Lechner. Validate the header size, reject an
underflowed length, ensure the resulting payload is contained in the
firmware image, and require it to contain whole register/value entries.

Fixes: 07b2412 ("iio: proximity: aw96103: Add support for aw96103/aw96105 proximity sensor")
Link: https://lore.kernel.org/r/20260314-iio-proximity-aw96103-fix-firmware-read-v1-1-c74fe9ccd82b@baylibre.com
Cc: stable@vger.kernel.org
Signed-off-by: Laxman Acharya Padhya <acharyalaxman8848@gmail.com>
Signed-off-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Changed files:
  drivers/iio/proximity/aw96103.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=4a9b9f2d4e26589afd0ac099c8e5593170dd5ac7

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

The original Linux kernel CVE announcement for CVE-2026-98658 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98658

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: AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
  The Best / paranoid CVSS vector: AV:L/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:H
  The Best / paranoid CVSS score: 5.6

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: MODERATE
KPANIC detected for this report: NO
Published priority for this report (same as in Subject): MODERATE REGULAR

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).