[CVE-2026-93799][MODERATE REGULAR] wifi: iwlwifi: mvm: validate sta_id in BA window status notif [ Upstream

[CVE-2026-93799][MODERATE REGULAR] wifi: iwlwifi: mvm: validate sta_id in BA window status notif [ Upstream

[AL-KERNEL]

CVE: CVE-2026-93799
Priority: MODERATE REGULAR
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: wifi: iwlwifi: mvm: validate sta_id in BA window status notif [ Upstream
Commit: bb08fbbbd5568d33069485ecb0a1657f115a4e9f
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=bb08fbbbd5568d33069485ecb0a1657f115a4e9f
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-93799
Analysis date: Thu, 24 Sep 2026 19:44:53 -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-2026-93799 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-93799

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.

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

CVE-2026-93799	MODERATE	https://www.kernelcve.org/list/?q=CVE-2026-93799 CHECK WITH IMPACT FROM ORIG NN IMPORTANT	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:H';CWE-125;CWE-129;*CWE-20;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '5.2';DESCR 'An insufficient bounds check in the Intel iwlwifi MVM driver allows a firmware supplied sta_id from a BA window status notification to index fw_id_to_mac_id outside the number of supported firmware station entries. The resulting value is treated as a station pointer and may cause a kernel crash if an invalid entry is processed. For the CVSS the PR:H because reliable triggering appears to require control of trusted device firmware or an equivalent privileged local hardware control condition. The issue is not directly network reachable from a normal WiFi peer because the affected value originates from a firmware notification rather than directly from an over the air frame. Impact is at least denial of service via kernel crash. Limited confidentiality or integrity impact is retained only in the paranoid score because the patch indicates an out of bounds pointer read, but it does not demonstrate a controlled write or a confirmed privilege escalation path. YES REQUIRES MANUAL CHECK.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 2)	YES	REMOTE WRITE OOB SIMPLEFIX NETWORK  LOWERED_FROM_HIGH_BASED_ON_GUESSCVSS  DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN4	NO	NO	checked

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

ActionableScore=2
PrimitiveClass=CLASS_C
RealUAF=NO
HostAdminRequired=UNKNOWN
NamespaceScopedPrivilege=UNKNOWN
ImportantCandidate=NO
ManualReview=RECOMMENDED
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 was applied.

2. Signal breakdown

* +1 Weak indirect corruption candidate. The firmware supplied 5 bit sta_id is used as an unchecked index to obtain a value later interpreted as a station pointer.
* +1 Plausible kernel DoS. An invalid non NULL entry can be treated as a struct ieee80211_sta pointer by subsequent code and can plausibly cause an invalid dereference or kernel fault.
* +0 Remote reachable. The value originates in a firmware notification. The supplied patch does not establish that an unauthenticated WiFi peer can cause firmware to emit an arbitrary invalid BA window status notification.
* +0 Firmware mediated external influence. Firmware mediation exists, but attacker influence over this particular notification is not established.
* +0 Local unprivileged trigger. No evidence establishes that an ordinary local user can control the relevant firmware notification.
* +0 Strong or weak LPE leverage. No controlled object replacement, controlled reclaim, arbitrary write, refcount mutation, callback control, or security boundary bypass is demonstrated.
* +0 Confidentiality and integrity. The patch shows no disclosure path, write primitive, or protected state modification.
* +0 Real UAF. No object release, free, stale lifetime use, or RCU lifetime violation is established.
* +0 Concrete repeated release or refcount mutation. No first lifetime ending operation and no later operation on the same dangling reference are shown.
* +0 Extra Availability. The possible kernel fault is already represented by the single DoS point.

The commit describes out of bounds indexing relative to firmware supported station entries. The supplied diff does not include the declaration and allocation size of fw_id_to_mac_id. Therefore it is not established from the provided evidence whether this is a physical C array out of bounds read or an invalid logical station slot lookup within a maximum sized array.

3. Reachability analysis

The immediate input is generated by Intel WiFi firmware and delivered through BA_WINDOW_STATUS_NOTIFICATION_ID processing. A normal remote WiFi peer does not directly invoke iwl_mvm_window_status_notif or directly supply sta_id to the kernel.

The supplied evidence does not establish whether malformed over the air traffic can induce a faulty firmware notification. It also does not establish a local userspace interface that can inject this notification without firmware compromise, privileged device manipulation, or a firmware defect.

Host admin privilege is therefore UNKNOWN, not YES. The available material does not prove that firmware replacement or privileged device control is necessary for every trigger, but it also does not prove a below host admin trigger. Namespace scoped privilege is UNKNOWN because no complete namespace reachable trigger chain is shown.

No special rare physical hardware penalty is applied. Intel iwlwifi hardware is broadly deployed, but the attacker controlled reachability of the malformed firmware notification remains unresolved.

4. Primitive and severity interpretation

The demonstrated primitive is an unchecked firmware supplied station identifier used to select an entry in fw_id_to_mac_id. The selected value is subsequently handled as a station pointer after IS_ERR_OR_NULL validation.

This is not an established UAF. There is no free, put, release, RCU retirement, stale post lifetime reference, or second lifetime mutation. There is also no demonstrated attacker controlled write, controlled replacement object, callback dispatch, information disclosure, or authorization bypass.

The appropriate classification is CLASS_C because the currently supported consequence is invalid state handling that may result in an invalid pointer dereference and kernel DoS. The patch alone does not establish meaningful exploitation leverage beyond that potential fault.

ImportantCandidate is NO because the evidence does not establish a Class A primitive or a strong unresolved Class B lifetime or corruption primitive. AutoDowngradeAllowed is YES because the available patch evidence supports a constrained invalid index and potential crash scenario, without demonstrated attacker controlled corruption or a security boundary consequence.

The likely operational severity is ordinary Moderate or lower priority until the fw_id_to_mac_id declaration, subsequent station pointer use, and firmware notification reachability are verified.

5. One-sentence report phrase

An unchecked firmware supplied station identifier can select an invalid iwlwifi station entry and may cause a kernel fault, but direct attacker control of the firmware notification and exploitation beyond denial of service are not established.

6. Manual review recommendation

MANUAL CHECK RECOMMENDED

Verify the actual fw_id_to_mac_id array bounds and all subsequent uses of sta. Also determine whether malformed WiFi traffic can cause firmware to generate an invalid BA window status notification without firmware compromise or privileged local device control.

7. Call-site confidence

Call-site confidence: low

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

Patch: wifi: iwlwifi: mvm: validate sta_id in BA window status notif [ Upstream
Commit: bb08fbbbd5568d33069485ecb0a1657f115a4e9f
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=bb08fbbbd5568d33069485ecb0a1657f115a4e9f

Changed files:
  drivers/net/wireless/intel/iwlwifi/mvm/rx.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=bb08fbbbd5568d33069485ecb0a1657f115a4e9f

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

The original Linux kernel CVE announcement for CVE-2026-93799 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-93799

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:H/UI:N/S:U/C:N/I:N/A:H
  The Best / paranoid CVSS vector: AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:H
  The Best / paranoid CVSS score: 5.2

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: 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).