[CVE-2026-98110][LOW] Bluetooth: btintel: bound firmware ID by TLV length [ Upstream

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

CVE: CVE-2026-98110
Priority: LOW
AL-KERNEL base severity: LOW
KPANIC flag: NO
Patch: Bluetooth: btintel: bound firmware ID by TLV length [ Upstream
Commit: aef56a2bd5aa22808ce508605d7497d2b5e8eb5f
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=aef56a2bd5aa22808ce508605d7497d2b5e8eb5f
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98110
Analysis date: Sat, 26 Sep 2026 15:14:02 -0400
ActionableScore: 1
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-2026-98110 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98110

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.

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

CVE-2026-98110	LOW	https://www.kernelcve.org/list/?q=CVE-2026-98110 CHECK WITH IMPACT FROM ORIG NN MODERATE	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:P/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L';CWE-125;CWE-170;*CWE-20;Other CVSS 'AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '3.5';DESCR 'An out of bounds read in the Intel Bluetooth firmware TLV parser occurs because the firmware ID value is treated as a NUL terminated string although the TLV length is its only valid boundary. A malformed firmware response without a NUL terminator can make snprintf read beyond the advertised TLV value and potentially beyond the received HCI response buffer. For the CVSS the PR:N rating reflects that no authenticated account or local user privileges are required after a malicious or compromised Bluetooth controller is attached. The issue is not directly reachable from a remote Bluetooth peer because the affected value is supplied by the local controller firmware response. The realistic attack scenario involves physical access to attach a malicious adapter or control over the local Bluetooth controller firmware. Impact is at least limited denial of service and the paranoid assessment includes limited confidentiality impact from unintended adjacent memory reads. No memory write or privilege escalation primitive is demonstrated.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 1)	YES	SIMPLEFIX  DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_GUESSCVSS	YES	NO	checked

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

ActionableScore=1
PrimitiveClass=CLASS_C
RealUAF=NO
HostAdminRequired=NO
NamespaceScopedPrivilege=UNKNOWN
ImportantCandidate=NO
ManualReview=RECOMMENDED
AutoDowngradeAllowed=YES

1. ActionableScore

* Raw conservative score: 1
* Conservative score: 1
* Raw paranoid score: 1
* Paranoid score: 1
* Final recommended bucket: **Ordinary Moderate**::

2. Signal breakdown

* +1 Firmware-mediated external influence. The affected TLV is supplied by the local Intel Bluetooth controller firmware response. A malicious or compromised local controller can provide a non-NUL-terminated TLV value.
* +0 Weak invalid-read concern. The patch establishes an out-of-bounds read through snprintf but does not establish a write, UAF, controlled reclaim, or active-object corruption.
* +0 Reliable kernel crash not awarded. The commit states that snprintf can read beyond the response, but does not demonstrate a reproducible kernel crash or panic.
* +0 Confidentiality not awarded. No user-visible disclosure path is shown. Reading unintended adjacent kernel memory does not by itself establish disclosure.
* +0 Integrity not awarded. The patch changes a read bound only. No write primitive, refcount mutation, or ownership violation is established.
* +0 Remote reachability not awarded. A remote Bluetooth peer does not directly construct the Intel controller firmware response parsed by this path.
* No host-admin penalty applied. A malicious physically attached or compromised controller can provide the malformed response without requiring host administrative credentials.
* No physical-only rare-hardware penalty applied. Intel Bluetooth controllers are common hardware, even though the practical attacker model requires physical access to the adapter or control over its firmware.

3. Reachability analysis

The affected value is received from a local Intel Bluetooth controller as part of a firmware/version TLV response. The supplied patch does not show that an ordinary nearby Bluetooth device can inject or spoof this vendor-specific controller response over the air.

The realistic attacker is a person with physical access who attaches a malicious Bluetooth adapter, replaces an existing adapter, or controls the firmware of the local controller. This does not require host-admin privileges after the malicious device is attached, therefore HostAdminRequired is NO.

No network namespace, user namespace, or namespace-scoped capability path is involved. NamespaceScopedPrivilege is UNKNOWN because namespaces are not relevant to the demonstrated trigger.

There is no demonstrated race, no prior privileged software setup requirement, and no special rare hardware requirement beyond the presence of a supported Intel Bluetooth controller.

4. Primitive and severity interpretation

The exact primitive is an out-of-bounds read. The parser passes tlv->val to snprintf using an unbounded string format, even though tlv->len is the only valid boundary. If the TLV value lacks a NUL terminator, snprintf can continue reading beyond the intended TLV value and potentially beyond the received HCI response buffer.

This is not a UAF, double release, refcount error, active structured-object lifetime issue, or ownership violation. The patch does not establish a kernel write, attacker-controlled target selection, controlled object reuse, callback influence, information disclosure path, or privilege-escalation mechanism.

The issue is classified as CLASS_C because the demonstrated behavior is an invalid read with at most a potential crash or limited unintended memory consumption. It is not CLASS_A or CLASS_B because no meaningful corruption or lifetime primitive is established.

ImportantCandidate is NO. The patch-supported consequence is limited and no exploitation leverage beyond the invalid read is shown. AutoDowngradeAllowed is YES because there is no unresolved UAF, write primitive, authorization bypass, boundary violation, or active-object corruption mechanism requiring Important-level review.

Likely operational severity is Low-like. It should be patched normally, especially on systems that permit untrusted physical peripherals, but it does not warrant urgent escalation based on the supplied evidence.

5. One-sentence report phrase

A malformed firmware ID TLV from a local Intel Bluetooth controller can cause an out-of-bounds read because the driver treats a length-bounded value as a NUL-terminated string, with no demonstrated write, disclosure, or privilege-escalation primitive.

6. Manual review recommendation

MANUAL CHECK RECOMMENDED

The issue is a concrete kernel out-of-bounds read, but the supplied evidence does not establish a crash, disclosure path, or attacker-controlled memory corruption. Review is useful to confirm controller-response reachability and whether fw_id can be exposed through logs or firmware-name construction.

7. Call-site confidence

Call-site confidence: medium

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

Patch: Bluetooth: btintel: bound firmware ID by TLV length [ Upstream
Commit: aef56a2bd5aa22808ce508605d7497d2b5e8eb5f
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=aef56a2bd5aa22808ce508605d7497d2b5e8eb5f

Changed files:
  drivers/bluetooth/btintel.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=aef56a2bd5aa22808ce508605d7497d2b5e8eb5f

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

The original Linux kernel CVE announcement for CVE-2026-98110 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98110

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:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
  The Best / paranoid CVSS vector: AV:P/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
  The Best / paranoid CVSS score: 3.5

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: 1

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).