[CVE-2025-71154][LOW] net: usb: rtl8150: fix memory leak on usb_submit_urb() failure [ Upstream

[CVE-2025-71154][LOW] net: usb: rtl8150: fix memory leak on usb_submit_urb() failure [ Upstream

[AL-KERNEL]

CVE: CVE-2025-71154
Priority: LOW
AL-KERNEL base severity: LOW
KPANIC flag: NO
Patch: net: usb: rtl8150: fix memory leak on usb_submit_urb() failure [ Upstream
Commit: a4e2442d3c48355a84463342f397134f149936d7
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=a4e2442d3c48355a84463342f397134f149936d7
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2025-71154
Analysis date: Mon, 12 Oct 2026 21:31:49 -0400
ActionableScore: 1
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-2025-71154 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2025-71154

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.

======================================================================
AL-KERNEL CLASSIFICATION RESULT
======================================================================

CVE-2025-71154	LOW	https://www.kernelcve.org/list/?q=CVE-2025-71154 CHECK WITH IMPACT FROM ORIG NN LOW | AEGIS IMPACT LOW AEGIS_AS=1 LEGACY=LOW RESULT=SAME (legacy and Aegis reconciliation agree; DECISION: both LOW)	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L';*CWE-401;*CWE-772;Other CVSS 'AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '2.5';DESCR 'The rtl8150 driver leaks an async request structure and an URB when usb_submit_urb() fails because the completion callback that normally releases them is never executed. Repeated failures could gradually consume kernel memory, but reliable accumulation requires repeated access to the specific submission failure path and is not established for ordinary network traffic. For the CVSS the PR:L value is used in the paranoid score because a local user or restricted service with delegated network interface control may be able to initiate repeated configuration operations while the USB device is failing. The base score uses PR:H because reliable manipulation of the device state normally requires administrative control. AC:H applies because successful abuse depends on repeatedly causing usb_submit_urb() to fail at the required point. The issue is not directly network reachable. Impact is limited to a potential local denial of service through gradual resource exhaustion, with no supported memory corruption, information disclosure, or privilege escalation primitive.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 1)	MAYBE	USB INIT SIMPLEFIX LEAK ERRORPATH NETWORK SYZBOT 	-	-	checked

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

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

1. ActionableScore

* Raw conservative score: 1
* Conservative score: 1
* Raw paranoid score: 1
* Paranoid score: 1
* No floor or cap was applied.
* Final recommended bucket: **Ordinary Moderate**::

2. Signal breakdown

* +1 Concrete persistent kernel resource leak. When `usb_submit_urb()` fails, the allocated `async_req` and URB become unreachable because the completion callback will never execute.
* No reliable kernel crash or strong DoS point. The patch establishes a small per-failure leak, not host-wide exhaustion.
* No additional resource-exhaustion point. Reliable and repeatable accumulation of the leaking branch is not established.
* No UAF, OOB access, double release, stale-object use, or memory overwrite is present.
* No remote-reachability point. Ordinary network traffic is not shown to force `usb_submit_urb()` failure.
* No local-unprivileged point. The complete caller and privilege path is not supplied.
* No privilege penalty. Host-admin-equivalent privilege is not positively established.
* No hardware penalty. An RTL8150-class USB device is a prerequisite, but this is not evidence of a physical attacker or rare-hardware attack.
* NEW52 B5-R does not apply because there is no heap OOB write, retry-accumulated index, or later consumption of corrupted state.
* NEW53 B3-PENDING does not apply because no shared-backing write occurs.
* NEW54 B4-PENDING does not apply because no authorization decision or mandatory security guard is involved.

3. Reachability analysis

The affected driver and a compatible USB network device must be present. An operation must reach `async_set_registers()`, and `usb_submit_urb()` must fail before ownership transfers to USB core. The supplied context does not establish whether an ordinary user, a delegated network-management service, or only an administrator can drive the complete sequence.

The submission failure may result from disconnect, shutdown, or resource pressure, but attacker control over that failure and repeatable accumulation is not demonstrated. This is not a timing race and is not directly network-triggerable. No namespace-scoped complete trigger chain is established, and no evidence shows that numeric host UID 0 is specifically required.

4. Primitive and severity interpretation

The exact defect is failure to release two allocations after unsuccessful URB submission. Because submission failed, the completion callback cannot run and the allocations are permanently lost.

This is a resource leak, not a post-lifetime access. Neither object is freed and subsequently used, and no second release or refcount mutation occurs. There is no corrupted state consumed by later kernel processing.

`PrimitiveClass=NONE` is appropriate because no corruption, stale-object, ownership, or authorization primitive is established. The demonstrated consequence is limited memory retention. Host-wide denial of service would require repeatable forced submission failures and sufficient accumulation, neither of which is supported.

`ImportantCandidate=NO` because there is no Important-preserving primitive or unresolved exploitation leverage. `AutoDowngradeAllowed=YES` because the issue is a constrained resource leak without memory corruption, boundary bypass, reliable exhaustion, or demonstrated low-privilege trigger.

5. One-sentence report phrase

The rtl8150 driver leaks an asynchronous request and URB when USB submission fails, but the evidence supports only a small conditional resource leak without a reliable host-wide denial of service path.

6. Manual review recommendation

NO MANUAL CHECK NEEDED

The concrete defect is fully explained by the missing error-path frees, with no evidence of corruption, authorization bypass, repeatable unprivileged exhaustion, or stronger security impact.

7. Call-site confidence

Call-site confidence: medium

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

Patch: net: usb: rtl8150: fix memory leak on usb_submit_urb() failure [ Upstream
Commit: a4e2442d3c48355a84463342f397134f149936d7
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=a4e2442d3c48355a84463342f397134f149936d7

Changed files:
  drivers/net/usb/rtl8150.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=a4e2442d3c48355a84463342f397134f149936d7

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

The original Linux kernel CVE announcement for CVE-2025-71154 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2025-71154

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:L
  The Best / paranoid CVSS vector: AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
  The Best / paranoid CVSS score: 2.5

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: 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).