[CVE-2026-98810][LOW] wifi: mac80211: fix slab-out-of-bounds read in ieee80211_monitor_select_queue() [ Upstream

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

CVE: CVE-2026-98810
Priority: LOW
AL-KERNEL base severity: LOW
KPANIC flag: NO
Patch: wifi: mac80211: fix slab-out-of-bounds read in ieee80211_monitor_select_queue() [ Upstream
Commit: 63e7064b4c1c4b540bf2f0cba47384f92ab95307
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=63e7064b4c1c4b540bf2f0cba47384f92ab95307
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98810
Analysis date: Sat, 24 Oct 2026 03:43:46 -0400
ActionableScore: 1
ActionableScore lower bound: 0
Actionable bucket: Ordinary Moderate
Manual review required: NO

Summary:
A capability-gated local monitor-packet injection can cause a slab OOB header read from a non-linear skb, with KASAN detection and possible configuration-dependent kernel crash but no shown disclosure or write.

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

The original Linux kernel CVE announcement for CVE-2026-98810 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98810

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-2026-98810	LOW	https://www.kernelcve.org/list/?q=CVE-2026-98810 CHECK WITH IMPACT FROM ORIG NN LOW | AEGIS IMPACT MODERATE_KPANIC AEGIS_AS=2 LEGACY=LOW RESULT=DIFF TEMP_DISTANCE_MERGE_SKIP=AEGIS_NO_POSITIVE_SEVERITY_EVIDENCE (final Legacy and Aegis differ; FINAL: LOW, Aegis: MODERATE_KPANIC)	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-125;*CWE-20;CWE-1284;Other CVSS 'AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '5.5';DESCR 'mac80211 monitor injection paths validated accesses using the total skb length even though the radiotap and 802.11 headers were dereferenced through the linear skb data buffer. A local AF_PACKET sender can create a sufficiently large non-linear skb whose total length passes validation while the required header extends beyond skb_headlen, causing a slab out of bounds read of fields such as frame_control. For the CVSS the PR:L value reflects the need for a local process with AF_PACKET and monitor injection access, normally through CAP_NET_RAW or delegated namespace capability. No OOB write, UAF, or proven information disclosure path is present. The demonstrated result is a KASAN report, while a kernel crash is a defensible worst case on configurations that panic on memory safety faults. Automated impact decision path. The original SimpleNet classifier selected LOW. The primary LLM estimated paranoid CVSS 5.5 and the production ActionableScore returned 1 with recommendation Ordinary Moderate. The production rules then evaluated CVSS thresholds and ActionableScore thresholds. Recorded rule transitions were final reconciliation stage LOW to LOW because KP specialist did not establish a qualifying panic and the cross model evidence reconciliation rule was applied. The legacy KP specialist has no review artifact for this run. The legacy FD or DH downgrade specialist has no review artifact for this run. Exact triggered rule markers were KPANIC_UNSUPPORTED_REMOVED and V64_AEGIS_UNSUPPORTED_PROMOTION_BLOCKED. The independent weaker Aegis shadow evaluated CVSS 3.3 and ActionableScore 2 with primitive class CLASS_C and manual review REQUIRED. Its independently reconciled impact was MODERATE_KPANIC. The models disagreed but the aggregation rules retained the production result. The final reported impact is LOW.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 1)	MAYBE	REMOTE READ KASAN OOB SKB SYZBOT PACKET KPANIC_UNSUPPORTED_REMOVED V64_AEGIS_UNSUPPORTED_PROMOTION_BLOCKED	-	-	checked

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

ActionableScore=1
ActionableScoreLower=0
PrimitiveClass=CLASS_C
RealUAF=NO
HostAdminRequired=NO
NamespaceScopedPrivilege=UNKNOWN
ImportantCandidate=NO
ManualReview=RECOMMENDED
AutoDowngradeAllowed=YES
RequiresHostUID0=NO
AuthorizationDecisionBypass=NO
ProtectedResourceImpact=NONE
B4PendingReview=NO
B4PendingConfirmed=NO

1. ActionableScore

* Raw base score: 0.
* Conservative score: 0; no floor or cap applied.
* Raw paranoid score: 1.
* Paranoid score: 1; no floor or cap applied.
* Final recommended bucket: **Ordinary Moderate**::

2. Signal breakdown

* **+1 weak read-only OOB concern:** total `skb->len` validates data that is dereferenced through the shorter linear `skb->data` area, permitting a slab-out-of-bounds read of radiotap/802.11 header fields.
* **-1 reduced privilege requirement:** the supplied evidence requires AF_PACKET and monitor-injection access, associated with CAP_NET_RAW or delegated access rather than ordinary unprivileged execution.
* **Paranoid +1 plausible kernel crash:** KASAN observed the invalid read; a fatal fault is defensible on panic-on-warning/fault configurations, but a reliable production panic is not established.
* No write, UAF, disclosure path, authorization bypass, corrupted active state, or later consumer of attacker-corrupted data is shown.
* NEW52/B5-R does not apply: there is no retry-accumulated OOB write.
* NEW53/B3-PENDING does not apply: no shared-backing write occurs.
* No confidentiality or integrity point is awarded merely because adjacent slab bytes are read internally.

3. Reachability analysis

A local process with AF_PACKET and access to a monitor-injection interface can supply a sufficiently large non-linear skb. Numeric host UID 0 and full host-administrator power are not required by the supplied model. CAP_NET_RAW may be delegated, but the evidence does not establish that monitor-interface creation and the complete setup are available entirely within attacker-created namespaces; therefore `NamespaceScopedPrivilege=UNKNOWN`. No timing race or special hardware is required beyond an applicable mac80211 monitor interface.

4. Primitive and severity reading

The primitive is a read past the allocated linear skb head into adjacent slab memory. It is neither a write nor a lifetime violation, and no bytes are copied back to userspace or transmitted as a disclosure. The demonstrated effect is a KASAN report; a crash is configuration-dependent. This is CLASS_C crash/invalid-read behavior, not an Important-preserving corruption primitive. Auto-downgrade is allowed because no material unknown write, ownership, authorization, or trust-boundary primitive remains.

5. One-sentence report phrase

A capability-gated local monitor-packet injection can cause a slab OOB header read from a non-linear skb, with KASAN detection and possible configuration-dependent kernel crash but no shown disclosure or write.

6. Manual review advice

MANUAL CHECK RECOMMENDED

Confirm product-specific monitor-interface delegation and fatal-fault policy; no Important-class primitive is presently shown.

7. Call-site confidence

Call-site confidence: high

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

Patch: wifi: mac80211: fix slab-out-of-bounds read in ieee80211_monitor_select_queue() [ Upstream
Commit: 63e7064b4c1c4b540bf2f0cba47384f92ab95307
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=63e7064b4c1c4b540bf2f0cba47384f92ab95307

Changed files:
  net/mac80211/iface.c
  net/mac80211/tx.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=63e7064b4c1c4b540bf2f0cba47384f92ab95307

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

The original Linux kernel CVE announcement for CVE-2026-98810 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-98810

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:L/UI:N/S:U/C:N/I:N/A:L
  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: 0
  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).