[CVE-2026-90345][MODERATE REGULAR] wifi: brcmfmac: fix P2P action frame handling without device vif [ Upstream

[CVE-2026-90345][MODERATE REGULAR] wifi: brcmfmac: fix P2P action frame handling without device vif [ Upstream

[AL-KERNEL]

CVE: CVE-2026-90345
Priority: MODERATE REGULAR
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: wifi: brcmfmac: fix P2P action frame handling without device vif [ Upstream
Commit: f26e1b16904555e171292e183c3cfc1c38159fc5
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=f26e1b16904555e171292e183c3cfc1c38159fc5
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-90345
Analysis date: Thu, 17 Sep 2026 15:03:36 -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-2026-90345 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-90345

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-2026-90345	MODERATE	https://www.kernelcve.org/list/?q=CVE-2026-90345 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-703;CWE-754;Other CVSS 'AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '5.5';DESCR 'brcmfmac P2P action frame handling can dereference a missing P2P device vif when non P2P public action frames are sent through the primary interface or when action frame abort runs before the P2P device vif exists. This can cause a NULL pointer dereference in the wireless driver and crash the kernel. For the CVSS the PR:L is used in the paranoid score because a delegated local process or service account with wireless management access may trigger the action frame path, even though full CAP_NET_ADMIN is typical in default setups. The issue is not proven to be directly network reachable because the affected paths are mainly driven by local userspace control plane operations. Impact is denial of service only via kernel crash. Nearby wireless interaction may be relevant in real deployments if it can influence the local supplicant or abort timing, so the exposure should be validated manually.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 2)	YES	REMOTE SIMPLEFIX NETWORK HARDWARE  DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS_AND_CIANNH	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 changed the score.

### 2. Signal breakdown

Positive signals:

* +1: Invalid object state / NULL pointer dereference. The P2P device `vif` may be absent, but the old code dereferenced it through `vif->ifp` or `vif->saved_ie`.
* +1: Reliable kernel crash / DoS. A NULL dereference in the wireless driver can plausibly crash the kernel.

Negative / non-awarded signals:

* +0: Real UAF not established. The patch shows missing NULL checks, not stale lifetime use.
* +0: Controlled reclaim not demonstrated.
* +0: Arbitrary write not demonstrated.
* +0: Confidentiality and integrity impact not awarded. The primitive is NULL dereference / crash only.
* +0: Direct remote reachability not established. The commit says userspace sends action frames.
* +0: Local unprivileged trigger not established. Wireless management operations commonly require a privileged supplicant or CAP_NET_ADMIN-like authority.
* +0: No race penalty. The abort timing is state-dependent, but no hard attacker-uncontrolled race is established.
* +0: No extra availability point. The same crash is already counted once.
* +0: No Important-grade exploitation leverage. No memory corruption, repeated refcount mutation, callback control, or security-boundary bypass is shown.

### 3. Reachability analysis

The visible trigger is through userspace-driven P2P / public action frame handling in `brcmfmac`. The commit mentions two reachable states: non-P2P public action frames sent through the primary interface, and action-frame abort before the P2P device `vif` exists.

The exact privilege boundary is not fully proven by the supplied patch. In typical systems, direct wireless management frame operations are mediated by privileged components such as `wpa_supplicant`, NetworkManager, or CAP_NET_ADMIN-controlled nl80211 paths. This supports `HostAdminRequired=UNKNOWN` rather than confidently `YES` or `NO`.

The complete trigger is not shown to be namespace-scoped. A physical wireless device and its management operations should not be assumed attacker-instantiable from an unprivileged namespace. Therefore `NamespaceScopedPrivilege=UNKNOWN`.

Nearby wireless interaction may influence local supplicant behavior in real deployments, but the patch does not establish that a remote peer alone can directly reach the vulnerable dereference. Manual validation of practical exposure is useful, but direct network reachability is not scored.

### 4. Primitive and severity interpretation

The exact primitive is a NULL pointer dereference due to assuming that `p2p->bss_idx[P2PAPI_BSSCFG_DEVICE].vif` always exists.

This is not an active structured UAF. It is not fixed stale storage. It is a missing object/state validation issue that leads to invalid dereference.

No concrete repeated release/refcount operation exists. There is no first lifetime operation that may free an object, no exact dangling reference surviving, and no second lifetime mutation through freed storage.

Primitive class is `CLASS_C`: demonstrated crash/DoS behavior without an independently useful corruption primitive.

Demonstrated consequence: kernel crash / local DoS in the wireless driver path.

Speculative consequence: none strongly supported beyond DoS. Privilege escalation is not supported by the patch.

`ImportantCandidate=NO` because there is no UAF, no controlled memory corruption, no authorization bypass, and no demonstrated path beyond crash.

`AutoDowngradeAllowed=YES` because this is a constrained NULL dereference with crash-only impact and no unresolved Important-grade primitive.

Likely operational severity: ordinary Moderate / Low-like, with manual reachability review recommended because wireless control-plane exposure can vary by product.

### 5. One-sentence report phrase

A missing P2P device vif check in brcmfmac P2P action frame handling can cause a NULL pointer dereference and kernel crash when userspace sends certain action frames or aborts before the P2P vif exists.

### 6. Manual review recommendation

MANUAL CHECK RECOMMENDED

Reason: the technical primitive is crash-only, but practical reachability depends on product-specific wireless management permissions and whether nearby wireless activity can indirectly drive the local userspace action-frame path.

### 7. Call-site confidence

Call-site confidence: medium

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

Patch: wifi: brcmfmac: fix P2P action frame handling without device vif [ Upstream
Commit: f26e1b16904555e171292e183c3cfc1c38159fc5
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=f26e1b16904555e171292e183c3cfc1c38159fc5

Changed files:
  drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.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=f26e1b16904555e171292e183c3cfc1c38159fc5

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

The original Linux kernel CVE announcement for CVE-2026-90345 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-90345

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: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: 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).