CVE-2026-23313

Analyzed Analyzed - Analysis Complete

Preempt Count Leak in Linux i40e Driver Causes SoftIRQ Issues

Publication date: 2026-03-25

Last updated on: 2026-05-26

Assigner: kernel.org

Description

In the Linux kernel, the following vulnerability has been resolved: i40e: Fix preempt count leak in napi poll tracepoint Using get_cpu() in the tracepoint assignment causes an obvious preempt count leak because nothing invokes put_cpu() to undo it: softirq: huh, entered softirq 3 NET_RX with preempt_count 00000100, exited with 00000101? This clearly has seen a lot of testing in the last 3+ years... Use smp_processor_id() instead.

CVSS Scores

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Meta Information

Published

2026-03-25

Last Modified

2026-05-26

Generated

2026-07-06

AI Q&A

2026-03-25

EPSS Evaluated

2026-07-05

NVD

CVE-2026-23313

EUVD

EUVD-2026-15256

Affected Vendors & Products

Vendor	Product	Version / Range
linux	linux_kernel	From 6.19 (inc) to 6.19.7 (exc)
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	From 6.13 (inc) to 6.18.17 (exc)
linux	linux_kernel	From 6.7 (inc) to 6.12.77 (exc)
linux	linux_kernel	From 6.2 (inc) to 6.6.136 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-UNKNOWN

Attack-Flow Graph

Executive Summary

This vulnerability is related to the Linux kernel's i40e driver, where a preempt count leak occurs in the napi poll tracepoint. Specifically, the use of get_cpu() in the tracepoint assignment increases the preempt count without a corresponding put_cpu() call to decrease it, causing an imbalance.

This leads to the system entering a softirq (software interrupt) state with an incorrect preempt count, which can affect kernel behavior and stability.

The fix replaces get_cpu() with smp_processor_id() to avoid this preempt count leak.

Impact Analysis

The preempt count leak caused by this vulnerability can lead to incorrect kernel preemption behavior during network packet processing.

This may result in system instability or unexpected behavior in the network driver, potentially affecting performance or causing kernel issues under certain workloads.

Mitigation Strategies

The vulnerability is fixed by replacing the use of get_cpu() with smp_processor_id() in the Linux kernel's i40e driver to avoid a preempt count leak.

To mitigate this vulnerability immediately, you should update your Linux kernel to a version that includes this fix.

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