[CVE-2026-80830][MODERATE 7.0] usb: core: Add lock to usb_wakeup_notification()

[CVE-2026-80830][MODERATE 7.0] usb: core: Add lock to usb_wakeup_notification()

[AL-KERNEL]

CVE: CVE-2026-80830
Priority: MODERATE 7.0
AL-KERNEL base severity: MODERATE
KPANIC flag: YES
Patch: usb: core: Add lock to usb_wakeup_notification()
Commit: a7a16167991c88016acef720927400404039d850
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=a7a16167991c88016acef720927400404039d850
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80830
Analysis date: Fri, 04 Sep 2026 17:55:21 -0400
ActionableScore: 5
ActionableScore lower bound: 2
Actionable bucket: Actionable Moderate at minimum
Manual review required: YES

Summary:
No one-sentence report phrase was found.

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

The original Linux kernel CVE announcement for CVE-2026-80830 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80830

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
======================================================================

CVE-2026-80830	MODERATE	https://www.kernelcve.org/list/?q=CVE-2026-80830 CHECK WITH IMPACT FROM ORIG NN MODERATE	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:P/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H';*CWE-416;CWE-362;CWE-667;Other CVSS 'AV:P/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H';BEST CVSS score: '6.4';DESCR 'A race in usb_wakeup_notification() can occur because the function accessed USB hub state without device_state_lock while hub_disconnect() uses that lock to protect teardown. The xHCI driver can call this path from IRQ context, so a wakeup notification may run concurrently with hub disconnect and dereference freed hub or port memory. For the CVSS the PR:N is used for the paranoid score because a malicious or controlled USB device can potentially trigger the hardware event without needing an account on the target system, although physical access to the USB bus is still required. The issue is not network reachable. Impact is at least denial of service via kernel crash, and in the worst still defensible interpretation it may allow confidentiality or integrity impact because this is a race based use after free candidate involving access to freed kernel objects.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Actionable Moderate at minimum (with actual score 4)	YES	LOCK DANGER USB RACE UAF HARDWARE LINUS KPANIC 	NO	NO	checked

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

ActionableScore=5
ActionableScoreLower=2

1. ActionableScore
* Conservative score: 2
* Paranoid score: 5
* Final recommended bucket: **Actionable Moderate at minimum**::

2. Signal breakdown
* Memory corruption, weak/indirect corruption candidate: +1. The patch explicitly prevents dereferencing freed memory, but no controlled reclaim or object replacement is shown.
* Real lifetime corruption: +1. This is a race between `usb_wakeup_notification()` and `hub_disconnect()` over USB hub lifetime/state.
* Reliable kernel crash / strong DoS: +1. A freed hub/port pointer dereference from IRQ context is a realistic crash path.
* Broad/default/common subsystem: +1. USB core and xHCI are common on affected systems.
* Weak LPE concern: +1 in paranoid scoring only. The code can write through stale hub state via `set_bit(portnum, hub->wakeup_bits)`, but no attacker-controlled reclaim primitive is demonstrated.
* Confidentiality impact plausible: +1 in paranoid scoring only. UAF on freed kernel objects can theoretically expose stale object state, but this is not demonstrated.
* Integrity impact plausible: +1 in paranoid scoring only. The stale `set_bit()` write makes limited freed-object corruption plausible, but not a proven arbitrary write.
* Hard or unreliable race / special timing required: -1. The issue depends on an IRQ wakeup notification racing with hub disconnect.
* Physical-only or rare hardware-only condition: -2. A practical unprivileged attack likely needs a malicious or controlled USB device or physical USB-bus influence, not a network path.

3. Reachability analysis
The most plausible trigger is a USB wakeup event from xHCI racing with hub removal or disconnect. No local account is necessarily required if the attacker controls a USB device, but physical access or device-level influence is required. Namespaces and containers do not materially improve reachability because the vulnerable path is in USB core hardware event handling, not a namespaced user API. USB/xHCI is broadly deployed, but exploitation requires tight timing and specific hardware events.

4. Severity interpretation
This is not an ordinary correctness fix because the commit explicitly mentions dereferencing freed memory and the patch serializes against `hub_disconnect()`. Realistic impact is most likely local/physical DoS through kernel crash. Theoretical impact can be higher because the stale object access includes a write to hub state, but the patch does not show controlled reclaim, callback control, type confusion, or arbitrary write. Therefore it is best treated as Actionable Moderate, not a clear Important-class issue.

5. One-sentence report phrase
A race in `usb_wakeup_notification()` can allow an xHCI IRQ wakeup path to access USB hub state concurrently with `hub_disconnect()`, causing freed-memory dereference and likely kernel crash, with limited but nonzero UAF-based corruption concern under a malicious or controlled USB device scenario.

6. Manual review recommendation
MANUAL CHECK REQUIRED. The bug is a race-based freed-memory dereference in USB core with a possible stale write through `hub->wakeup_bits`, so it should not be auto-closed even though realistic exploitation is constrained by physical access and timing.

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

Patch: usb: core: Add lock to usb_wakeup_notification()
Commit: a7a16167991c88016acef720927400404039d850
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=a7a16167991c88016acef720927400404039d850

Commit description:

Add a spin lock to usb_wakeup notification to prevent a race condition
with dereferencing freed memory. This could be hit by the xHCI driver as
it calls this function from an IRQ and could race with the
hub_disconnect() function, which properly grabs this lock to protect the
state of the device.

Assisted-by: gkh_clanker_t1000
Signed-off-by: Griffin Kroah-Hartman <griffin@kroah.com>
Link: https://patch.msgid.link/20260713-usb_core_patches_1-v1-3-7721c2b33f53@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Changed files:
  drivers/usb/core/hub.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=a7a16167991c88016acef720927400404039d850

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

The original Linux kernel CVE announcement for CVE-2026-80830 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80830

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:P/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
  The Best / paranoid CVSS vector: AV:P/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
  The Best / paranoid CVSS score: 6.4

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: 2
  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: 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).