[CVE-2026-98333][MODERATE 7.0] wifi: mac80211: reset the LED state when ifup fails [ Upstream

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

CVE: CVE-2026-98333
Priority: MODERATE 7.0
AL-KERNEL base severity: MODERATE
KPANIC flag: YES
Patch: wifi: mac80211: reset the LED state when ifup fails [ Upstream
Commit: de6f9561db572df86d65c05545eb2397313bb8a5
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=de6f9561db572df86d65c05545eb2397313bb8a5
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98333
Analysis date: Sat, 10 Oct 2026 05:33:37 -0400
ActionableScore: 4
ActionableScore lower bound: unknown
Actionable bucket: Borderline / manual review recommended
Manual review required: YES

Summary:
No one-sentence report phrase was found.

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

The original Linux kernel CVE announcement for CVE-2026-98333 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98333

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 7.0
Manual review required: YES

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

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

CVE-2026-98333	MODERATE	https://www.kernelcve.org/list/?q=CVE-2026-98333 CHECK WITH IMPACT FROM ORIG NN LOW | AEGIS IMPACT MODERATE_KPANIC AEGIS_AS=2 LEGACY=MODERATE_KPANIC RESULT=SAME (legacy and Aegis reconciliation agree; DECISION: both MODERATE_KPANIC)	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H';*CWE-416;CWE-362;CWE-404;Other CVSS 'AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:H';BEST CVSS score: '7';DESCR 'mac80211 can leave the throughput LED trigger timer active when the first interface ifup operation fails. A later ieee80211_unregister_hw() path can free the LED state while the timer remains active, creating a credible timer use-after-free condition in tpt_trig_timer() rather than only a resource leak. Triggering requires a supported wireless device, failure of the first interface open operation, and subsequent hardware unregister or driver removal while the timer is pending. For the CVSS the PR:L value is used because a local user or service with delegated network administration capability can initiate interface state changes without requiring unrestricted host root. The issue is not directly network reachable through wireless packets. Impact is at least local denial of service through a kernel warning or crash and may include confidentiality and integrity impact if the freed timer storage is reused before the callback executes. Manual review is required because the observed free of an active timer provides a plausible memory corruption and privilege escalation path.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Borderline / manual review recommended (with actual score 4)	MAYBE	REMOTE DANGER SIMPLEFIX ERRORPATH HARDWARE SYZBOT KPANIC 	-	-	checked

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

ActionableScore=4
PrimitiveClass=CLASS_B
RealUAF=YES
HostAdminRequired=UNKNOWN
NamespaceScopedPrivilege=UNKNOWN
ImportantCandidate=NO
ManualReview=RECOMMENDED
AutoDowngradeAllowed=YES
RequiresHostUID0=UNKNOWN
AuthorizationDecisionBypass=NO
ProtectedResourceImpact=NONE
B4PendingReview=NO
B4PendingConfirmed=NO

1. ActionableScore

* Raw conservative score: 3
* Conservative score: 4
* Raw paranoid score: 3
* Paranoid score: 4
* Applied conservative REAL UAF FLOOR 4: 3 -> 4
* Applied paranoid REAL UAF FLOOR 4: 3 -> 4
* Final recommended bucket: **Borderline / manual review recommended**::

2. Signal breakdown

* +2 Real UAF / active lifetime violation. A TPT timer remains active after failed first ifup, while ieee80211_led_exit() can free its containing LED-trigger state.
* +1 Reliable kernel crash concern. A pending timer callback can execute against released storage and cause an Oops or host crash.
* +0 Structured stale-object leverage. The timer belongs to an active structured object, but controlled reclaim, attacker-shaped replacement contents, callback-target influence, or useful pointer manipulation is not established.
* +0 Attacker-influenced lifetime manipulation. Interface activation may influence initial state, but the evidence does not establish that one below-host-admin actor controls the failed open, object release, and post-free callback sequence.
* +0 Concrete repeated release/refcount. No first release followed by a second put, free, or refcount mutation through the exact same dangling reference is shown.
* +0 Remote reachability. Network packets do not directly reach the vulnerable transition.
* +0 Confidentiality and integrity. No disclosure, directed write, protected-object modification, or privilege escalation primitive is demonstrated.
* +0 Extra Availability. The same potential kernel crash is not counted twice.
* No timing penalty. This is an asynchronous ordered error and teardown sequence, but the supplied evidence does not prove a narrow or difficult race.
* No privilege penalty. Host-admin-equivalent privilege for the complete sequence is not positively established.
* B5-R is not applicable. There is no retry-accumulated heap OOB write.
* B3-PENDING is not applicable. There is no shared-backing write.
* B4-PENDING is not applicable. There is no authorization decision or DENY-to-ALLOW transition.

3. Reachability analysis

The vulnerable state starts when the first mac80211 interface is opened and that operation fails after activating the radio LED and TPT timer. The later lifetime transition occurs during hardware unregister or driver removal.

Interface state changes normally involve network-administration authority, but the exact governing namespace and complete privilege chain are not shown. More importantly, control over ifup does not by itself establish control over ieee80211_unregister_hw() or driver removal. Therefore HostAdminRequired and NamespaceScopedPrivilege remain UNKNOWN rather than being inferred as YES or NO.

The object is instantiated as part of mac80211 driver and hardware registration. Supported wireless hardware and a driver path capable of failing the first interface open are prerequisites. No special sysctl or boot option is identified. The rt2x00 trace demonstrates a real hardware-backed path, but it does not justify a rare-hardware penalty.

The sequence is asynchronous because a timer remains pending across teardown. It is not scored as a hard race because the patch describes persistent active state rather than a proven narrow, low-probability interleaving.

4. Primitive and severity interpretation

The exact primitive is an active timer surviving beyond the lifetime of its containing LED-trigger state. Because the timer remains registered when that state is freed, its later callback is a directly implied post-lifetime use. This is an active structured-object UAF rather than a resource leak or passive bookkeeping error.

The demonstrated vulnerable lifetime transition occurs in failed-open cleanup followed by hardware unregister or driver removal. No concrete repeated free, put, or refcount mutation on the same dangling reference exists. This is therefore category A, an ordinary asynchronous stale callback after cleanup, rather than category B, a second lifetime mutation through a dangling reference.

PrimitiveClass is CLASS_B because a real kernel lifetime violation exists. It is not CLASS_A because controlled reclaim, directed corruption, attacker-controlled callback state, arbitrary read or write, and privilege escalation are not established.

The practical demonstrated concern is warning, Oops, or kernel crash. A stronger consequence would require useful reuse of the freed allocation before the timer callback and meaningful consumption of replacement fields. That remains speculative.

ImportantCandidate is NO because the available evidence describes a constrained unregister or teardown UAF without independently useful exploitation leverage. AutoDowngradeAllowed is YES because there is no repeated lifetime mutation, authorization bypass, controlled reclaim, shared-page violation, or other unresolved Important-preserving primitive. The likely operational severity is Borderline or Moderate, with manual source review recommended due to the real active-timer UAF.

5. One-sentence report phrase

A failed first mac80211 interface open can leave the TPT LED timer active until its containing state is freed during hardware unregister, creating a cleanup-path timer use-after-free with a realistic kernel crash consequence but no demonstrated exploitation primitive beyond denial of service.

6. Manual review recommendation

MANUAL CHECK RECOMMENDED

The active timer establishes a real UAF, but current evidence supports a constrained cleanup or unregister crash path and does not establish controlled reuse, repeated lifetime mutation, or privilege escalation.

7. Call-site confidence

Call-site confidence: medium

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

Patch: wifi: mac80211: reset the LED state when ifup fails [ Upstream
Commit: de6f9561db572df86d65c05545eb2397313bb8a5
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=de6f9561db572df86d65c05545eb2397313bb8a5

Changed files:
  net/mac80211/led.c
  lib/debugobjects.c
  mm/slub.c
  net/mac80211/main.c
  net/mac80211/iface.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=de6f9561db572df86d65c05545eb2397313bb8a5

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

The original Linux kernel CVE announcement for CVE-2026-98333 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98333

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:H/PR:L/UI:N/S:U/C:L/I:L/A:H
  The Best / paranoid CVSS vector: AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
  The Best / paranoid CVSS score: 7

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: 4

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: YES
Published priority for this report (same as in Subject): MODERATE 7.0

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).