[CVE-2026-72352][MODERATE 7.0] HID: bpf: Fix hid_bpf_get_data() range check [ Upstream

[CVE-2026-72352][MODERATE 7.0] HID: bpf: Fix hid_bpf_get_data() range check [ Upstream

[AL-KERNEL]

CVE: CVE-2026-72352
Priority: MODERATE 7.0
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: HID: bpf: Fix hid_bpf_get_data() range check [ Upstream
Commit: ca373549140dfb386aa2de38364b58441b1f4885
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=ca373549140dfb386aa2de38364b58441b1f4885
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72352
Analysis date: Sun, 16 Aug 2026 00:59:52 -0400
ActionableScore: 6
ActionableScore lower bound: 4
Actionable bucket: Strong Important candidate / Actionable Moderate at minimum
Manual review required: YES

Summary:
An unsigned overflow in `hid_bpf_get_data()` can make HID-BPF return a pointer for a range outside the allocated context buffer, creating a local OOB access primitive with possible kernel crash, information disclosure, or privilege escalation impact when the affected BPF path is reachable.

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

The original Linux kernel CVE announcement for CVE-2026-72352 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72352

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-2026-72352	MODERATE	CHECK WITH IMPACT FROM ORIG NN LOW	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H';CWE-190;*CWE-787;CWE-125;Other CVSS 'AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H';BEST CVSS score: '7.8';DESCR 'hid_bpf_get_data used an unsigned range check based on rdwr_buf_size plus offset before returning a pointer into the HID-BPF context data. A very large size can wrap the computed end below ctx allocated_size and make the helper return a pointer even though the requested range is outside the backing buffer. This gives a local HID-BPF program a potential out-of-bounds access primitive in kernel memory rather than a simple crash-only condition. For the CVSS the PR:L is used in the paranoid score because practical deployments may delegate BPF or HID control to a non-root service account, container root, or a user with limited capabilities rather than full system administrator privileges. The issue is not network reachable and requires local ability to load or run the affected HID-BPF program path. Impact is potential memory corruption with denial of service and possible privilege escalation, so manual review is needed.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Strong Important candidate / Actionable Moderate at minimum (with actual score 5)	YES	USB BPF SIMPLEFIX HARDWARE LINUS  INCREASED_FROM_LOW_BASED_ON_REQUIREMANUALCHECK DECREASED_TO_MODERATEREG_BASED_ON_FALSEPOSCHECKOFKP	YES	NO	checked

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ACTIONABLESCORE ANALYSIS
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ActionableScore=6
ActionableScoreLower=4

## 1. ActionableScore

* Conservative score: **4**
* Paranoid score: **6**
* Final recommended bucket: **Strong Important candidate / Actionable Moderate at minimum**::

## 2. Signal breakdown

Conservative signals:

* **Generic memory corruption: +2**. The helper can return a pointer for a range not contained in the HID-BPF backing buffer due to unsigned addition wraparound. This is a plausible OOB access primitive.
* **Reliable kernel crash / strong DoS: +1**. An invalid pointer returned to a BPF program can plausibly cause kernel crash if dereferenced.
* **Confidentiality impact plausible: +1**. OOB read from adjacent kernel memory is plausible from the bug class, although not demonstrated.
* **Integrity impact plausible: +1**. OOB write is plausible if the returned pointer is used for writable access.
* **Privileged kernel/device-management memory corruption path: +1**. The bug is in HID-BPF device event data handling inside a trusted kernel driver path.
* **Requires admin/root/CAP_BPF/CAP_SYS_ADMIN in typical deployments: -2**. In the evaluated product model, unprivileged BPF is disabled and HID-BPF program loading is privileged.

Paranoid additions:

* **Local low-privileged trigger in delegated environments: +1**. If HID-BPF or BPF control is delegated to a reduced-capability service, container root, or non-full-root account, the practical PR becomes closer to PR:L.
* **Weak-to-moderate LPE concern: +1**. The primitive is an OOB pointer into kernel memory, which can support privilege escalation concerns, but the patch does not show attacker-controlled reclaim, arbitrary target selection, or a demonstrated exploit.

BPF gating cap applied:

* Conservative score capped at **5**, actual conservative result **4**.
* Paranoid score capped at **6**, actual paranoid result **6**.

## 3. Reachability analysis

The bug is local, not network reachable. Triggering requires the ability to load or run an affected HID-BPF program path and to call `hid_bpf_get_data()` with attacker-controlled `offset` and `rdwr_buf_size`.

In typical hardened/product configurations, this requires root or capabilities such as `CAP_BPF`, `CAP_SYS_ADMIN`, or equivalent HID/BPF management privileges, so conservative scoring applies the privileged-access penalty. Namespace or container setups may lower the practical barrier if BPF/HID control is delegated to container root or a reduced-capability service account, which justifies the higher paranoid score.

The path is not a broad default unprivileged interface. It is nevertheless security-relevant because it returns a kernel pointer after a broken bounds check.

Call-site confidence: **medium**. The changed helper and its return semantics are visible, but full caller behavior is not included in the supplied patch.

## 4. Severity interpretation

This is not an ordinary crash-only Moderate. The bug is an integer overflow in a range check that can return an out-of-bounds pointer into HID-BPF context data, so it has plausible kernel memory corruption implications.

Realistic exploitation is constrained by BPF privilege gating in typical deployments. Without delegated BPF access or a demonstrated exploit, the conservative result is borderline/manual-review level. With delegated BPF access or a writable OOB use at call sites, it becomes an Actionable Moderate and potential Important candidate.

## 5. One-sentence report phrase

An unsigned overflow in `hid_bpf_get_data()` can make HID-BPF return a pointer for a range outside the allocated context buffer, creating a local OOB access primitive with possible kernel crash, information disclosure, or privilege escalation impact when the affected BPF path is reachable.

## 6. Manual review recommendation

**MANUAL CHECK REQUIRED**

Reason: this is a bounds-check integer overflow that can produce an OOB kernel pointer. Even though typical deployments require privileged BPF/HID access, the primitive is stronger than a simple DoS and should not be auto-closed without checking caller writeability, verifier constraints, and product-specific BPF exposure.

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

Patch: HID: bpf: Fix hid_bpf_get_data() range check [ Upstream
Commit: ca373549140dfb386aa2de38364b58441b1f4885
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=ca373549140dfb386aa2de38364b58441b1f4885

Changed files:
  drivers/hid/bpf/hid_bpf_dispatch.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=ca373549140dfb386aa2de38364b58441b1f4885

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

The original Linux kernel CVE announcement for CVE-2026-72352 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-72352

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:H/I:H/A:H
  The Best / paranoid CVSS vector: AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
  The Best / paranoid CVSS score: 7.8

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: 4
  Paranoid ActionableScore: 6

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).