SB20260727133 - Race condition in Linux kernel hw epf driver



SB20260727133 - Race condition in Linux kernel hw epf driver

Published: July 27, 2026

Security Bulletin ID SB20260727133
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Denial of service

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Race condition (CVE-ID: CVE-2026-64430)

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper resource access in the ntb_epf_vec_isr interrupt handler in drivers/ntb/hw/epf/ntb_hw_epf.c when handling interrupts and deriving the vector number through pci_irq_vector() in hardirq context. A local user can trigger the vulnerable interrupt handling path to cause a denial of service.

The issue can result in "scheduling while atomic" kernel splats because pci_irq_vector() reaches code that takes a mutex in hardirq context.


Remediation

Install update from vendor's website.