[CVE-2026-90060][LOW] ALSA: control: Don't add invalid kcontrols to LED layer [ Upstream

[CVE-2026-90060][LOW] ALSA: control: Don't add invalid kcontrols to LED layer [ Upstream

[AL-KERNEL]

CVE: CVE-2026-90060
Priority: LOW
AL-KERNEL base severity: LOW
KPANIC flag: NO
Patch: ALSA: control: Don't add invalid kcontrols to LED layer [ Upstream
Commit: 6e152cbfac3a2a62f79df7d23d621917c20367eb
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6e152cbfac3a2a62f79df7d23d621917c20367eb
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-90060
Analysis date: Thu, 17 Sep 2026 13:16:31 -0400
ActionableScore: 2
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-2026-90060 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-90060

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-2026-90060	LOW	https://www.kernelcve.org/list/?q=CVE-2026-90060 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:L/UI:N/S:U/C:N/I:N/A:H';**CWE-476;*CWE-20;CWE-754;BEST CVSS score: '5.5';DESCR 'The ALSA control LED layer can dereference a NULL callback because it may attach a write only kcontrol that does not provide valid info or get callbacks. A local user with access to ALSA control interfaces can create or expose such a user control and trigger the LED notification path, leading to an Oops or kernel crash. For the CVSS the PR:L is used because local code execution and access to the ALSA control device are required, but full administrative privileges are not necessarily required when user controls are available. The issue is not network reachable and is not triggered by remote audio traffic. Impact is denial of service only because the observed primitive is a NULL pointer dereference, with no supported path to information disclosure or privilege escalation.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 2)	YES	DANGER NULLPTR SIMPLEFIX HARDWARE LINUS SYZBOT  DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS_AND_CIANNH DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3	NO	NO	checked

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

ActionableScore=2
PrimitiveClass=CLASS_C
RealUAF=NO
HostAdminRequired=NO
NamespaceScopedPrivilege=NO
ImportantCandidate=NO
ManualReview=NO
AutoDowngradeAllowed=YES

1. ActionableScore

* Raw conservative score: 2
* Conservative score: 2
* Raw paranoid score: 2
* Paranoid score: 2
* Final recommended bucket: **Ordinary Moderate**::

No floor or cap changed the score.

2. Signal breakdown

Positive signals:

* +1 Local below-host-admin trigger: the commit says even a user element can create the invalid write-only kcontrol state, so full host-admin privilege is not established as required.
* +1 Reliable kernel crash / strong DoS: the invalid kcontrol can lead to a NULL dereference in the snd_ctl_led_notify() call chain and an Oops.

Non-awarded signals:

* +0 Real UAF: no freed or stale post-lifetime object use is established.
* +0 Strong or weak LPE leverage: no controlled reclaim, arbitrary write, callback hijack from attacker-controlled memory, refcount corruption, or privilege escalation path is shown.
* +0 Confidentiality and integrity: NULL callback dereference supports crash only, not disclosure or unauthorized modification.
* +0 Remote reachability: ALSA control and LED-layer configuration are local interfaces, not network packet processing.
* +0 Extra availability: the same Oops/kernel crash is already counted once.
* +0 Resource leak: no persistent resource or reference leak is shown.
* +0 Race/timing penalty: no race is required.
* +0 Host-admin penalty: below-host-admin reachability is directly indicated by the user element statement.

3. Reachability analysis

The likely attacker is a local user or local process with access to ALSA control interfaces. The commit explicitly notes that even a user element can be write-only and lack a get callback, which supports below-host-admin reachability. This is not namespace-scoped. No network trigger is indicated. No special hardware beyond an affected ALSA control/LED-layer setup is required by the supplied evidence. No race or narrow timing condition is described.

HostAdminRequired is NO because the supplied commit text establishes that a user-created control element can participate in the vulnerable state. NamespaceScopedPrivilege is NO because the trigger is not based on namespace capabilities.

4. Primitive and severity interpretation

The primitive is an invalid NULL callback dereference. It is not an active-object UAF, not fixed stale storage, and not a repeated release/refcount mutation. The demonstrated consequence is an Oops/kernel crash caused when the LED layer assumes an associated kcontrol is readable and has valid info/get callbacks.

PrimitiveClass is CLASS_C because the established behavior is crash/DoS from invalid state without an independently useful corruption or ownership primitive. ImportantCandidate is NO because there is no evidence of memory corruption beyond NULL dereference, no UAF, no OOB access, no arbitrary write, no disclosure, no security-boundary bypass, and no plausible LPE primitive supported by the patch. AutoDowngradeAllowed is YES because the issue is a constrained local DoS and no unresolved Important-grade primitive remains.

Likely operational severity: ordinary local denial of service.

5. One-sentence report phrase

A local user with access to ALSA control interfaces may create or expose a write-only kcontrol without valid info or get callbacks, causing the ALSA control LED notification path to dereference a NULL callback and crash the kernel.

6. Manual review recommendation

NO MANUAL CHECK NEEDED

Reason: this is a local NULL pointer dereference DoS with no UAF, no concrete memory corruption primitive, no network reachability, and no supported privilege-escalation path.

7. Call-site confidence

Call-site confidence: high

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

Patch: ALSA: control: Don't add invalid kcontrols to LED layer [ Upstream
Commit: 6e152cbfac3a2a62f79df7d23d621917c20367eb
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6e152cbfac3a2a62f79df7d23d621917c20367eb

Changed files:
  sound/core/control_led.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=6e152cbfac3a2a62f79df7d23d621917c20367eb

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

The original Linux kernel CVE announcement for CVE-2026-90060 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-90060

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:L/UI:N/S:U/C:N/I:N/A:H
  The Best / paranoid CVSS score: 5.5

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: 2

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).