[CVE-2026-68414][MODERATE 7.0] wifi: cfg80211: cancel sched scan results work on unregister [ Upstream

[CVE-2026-68414][MODERATE 7.0] wifi: cfg80211: cancel sched scan results work on unregister [ Upstream

[AL-KERNEL]

CVE: CVE-2026-68414
Priority: MODERATE 7.0
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: wifi: cfg80211: cancel sched scan results work on unregister [ Upstream
Commit: 3368457b4871ae8f0f88d19c9a3e6270e850ede6
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=3368457b4871ae8f0f88d19c9a3e6270e850ede6
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68414
Analysis date: Mon, 10 Aug 2026 15:17:58 -0400
ActionableScore: 5
ActionableScore lower bound: 3
Actionable bucket: Strong Important candidate / Actionable Moderate at minimum
Manual review required: YES

Summary:
A race in cfg80211 scheduled scan result handling can leave `sched_scan_res_wk` running across `wiphy_unregister()` and `cfg80211_dev_free()`, causing a use-after-free of `rdev` state and at least a local kernel crash risk, with paranoid triage warranted due to kernel lifetime corruption.

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

The original Linux kernel CVE announcement for CVE-2026-68414 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68414

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.

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AL-KERNEL CLASSIFICATION RESULT
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CVE-2026-68414	MODERATE	CHECK WITH IMPACT FROM ORIG NN MODERATE	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-667;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '7';DESCR 'A race in cfg80211 scheduled scan result handling can leave sched_scan_res_wk queued or running while wiphy_unregister frees the containing rdev object. The worker later recovers rdev, locks the wiphy, and walks freed state, which was reproduced as a KASAN use-after-free in cfg80211_sched_scan_results_wk. For the CVSS the PR:L is used for the paranoid score because a local user or service with delegated wireless management or CAP_NET_ADMIN may be able to combine scheduled scan activity with device teardown in some deployments. The issue is not directly network reachable. Remote WiFi scan environment can influence scan results, but reliable triggering depends on local control plane activity and unregister or teardown of the wireless device. Impact is at least local denial of service via kernel crash. In the worst case, the UAF on kernel object state may allow confidentiality or integrity impact and should be reviewed manually.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Strong Important candidate / Actionable Moderate at minimum (with actual score 4)	YES	REMOTE READ DANGER UAF  INCREASED_TO_MODERATE7_BASED_ON_GUESSCVSS DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN5	NO	NO	checked

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

ActionableScore=5
ActionableScoreLower=3

## 1. ActionableScore

* Conservative score: 3
* Paranoid score: 5
* Final recommended bucket: **Strong Important candidate / Actionable Moderate at minimum**::

## 2. Signal breakdown

Conservative signals:

* Memory corruption, weak primitive: +1. The KASAN report confirms a race based use after free in `cfg80211_sched_scan_results_wk`, but the shown access is a read of freed `rdev` state and the patch does not show attacker controlled reclaim, write after free, type confusion, callback control, or refcount takeover.
* Real lifetime corruption: +1. A queued or running work item can outlive `wiphy_unregister()` and cross into `cfg80211_dev_free()`, leaving stale access to freed `cfg80211_registered_device` state.
* Reliable kernel crash / strong DoS: +1. The report shows a reproducible KASAN UAF in a cfg80211 workqueue path, and a production kernel could plausibly Oops or crash.
* Firmware or device mediated external influence: +1. The result notification comes from wireless scheduled scan activity, which may be influenced by driver or RF scan results, but this is not a direct remote network trigger.
* Broad/common subsystem exposure: +1. cfg80211 is a common WiFi subsystem on client systems.
* Hard or unreliable race / special timing required: -1. Triggering requires overlap between scheduled scan result work and unregister/free.
* Requires admin/root/CAP_NET_ADMIN/device teardown in typical deployments: -2. Reliable triggering normally requires local control over wireless device teardown, driver removal, or unregister paths.

Conservative total: 3

Paranoid adjustment:

* Privilege penalty refined to -1 instead of -2. In some deployments, wireless management may be delegated to a service, desktop user path, container-like environment, or reduced capability process rather than full host root.
* Availability impact realistic: +1. The stale workqueue UAF occurs in kernel object lifetime handling and can plausibly cause a host-wide crash rather than only a local failed operation.

Paranoid total: 5

## 3. Reachability analysis

The bug is local control-plane reachable, not directly network reachable. A remote WiFi environment can influence whether scheduled scan results exist, but the critical race requires local scheduled scan activity plus unregister or teardown of the wireless device. In typical deployments, unregister, module removal, device teardown, or similar operations require root or CAP_NET_ADMIN, so conservative reachability is privileged local.

Namespaces and containers may reduce the effective privilege assumption only if a workload is given delegated network or wireless management over the affected wiphy. That is not the common default, but it is plausible enough for paranoid triage to avoid auto-closing. The affected subsystem is common on WiFi-enabled systems, but the exact race window is narrow.

Call-site confidence: high. The patch directly shows the missing `cancel_work_sync(&rdev->sched_scan_res_wk)` in `wiphy_unregister()`, and the commit explains the queued work crossing the unregister/free boundary.

## 4. Severity interpretation

This behaves more like an actionable Moderate than an ordinary Moderate. The demonstrated primitive is a real kernel UAF, but it is race-dependent and currently shows stale read/access rather than a proven attacker-controlled reclaim or write primitive. Realistic impact is kernel crash or DoS.

Theoretical escalation cannot be fully dismissed because the stale object is kernel heap state and the worker walks freed `rdev` state. However, the patch does not show a concrete LPE primitive such as controlled object replacement, arbitrary write, callback hijack, or refcount takeover. Therefore the conservative score stays below Important, while the paranoid score reaches the Actionable Moderate range and requires manual review.

## 5. One-sentence report phrase

A race in cfg80211 scheduled scan result handling can leave `sched_scan_res_wk` running across `wiphy_unregister()` and `cfg80211_dev_free()`, causing a use-after-free of `rdev` state and at least a local kernel crash risk, with paranoid triage warranted due to kernel lifetime corruption.

## 6. Manual review recommendation

MANUAL CHECK REQUIRED

This is not a simple warning or resource leak. It is a confirmed race based kernel UAF in a common wireless subsystem, and although exploitation beyond DoS is not demonstrated, the lifetime corruption class is risky enough that it should not be auto-closed.

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

Patch: wifi: cfg80211: cancel sched scan results work on unregister [ Upstream
Commit: 3368457b4871ae8f0f88d19c9a3e6270e850ede6
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=3368457b4871ae8f0f88d19c9a3e6270e850ede6

Changed files:
  kernel/workqueue.c
  net/wireless/core.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=3368457b4871ae8f0f88d19c9a3e6270e850ede6

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

The original Linux kernel CVE announcement for CVE-2026-68414 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-68414

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: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: 3
  Paranoid ActionableScore: 5

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 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).