Use After Free Affecting kernel-zfcpdump-modules-internal package, versions *


Severity

Recommended
low

Based on Red Hat Enterprise Linux security rating.

Threat Intelligence

EPSS
0.03% (9th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications

Snyk Learn

Learn about Use After Free vulnerabilities in an interactive lesson.

Start learning
  • Snyk IDSNYK-RHEL9-KERNELZFCPDUMPMODULESINTERNAL-12530114
  • published6 Sept 2025
  • disclosed5 Sept 2025

Introduced: 5 Sep 2025

CVE-2025-39721  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

There is no fixed version for RHEL:9 kernel-zfcpdump-modules-internal.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel-zfcpdump-modules-internal package and not the kernel-zfcpdump-modules-internal package as distributed by RHEL. See How to fix? for RHEL:9 relevant fixed versions and status.

In the Linux kernel, the following vulnerability has been resolved:

crypto: qat - flush misc workqueue during device shutdown

Repeated loading and unloading of a device specific QAT driver, for example qat_4xxx, in a tight loop can lead to a crash due to a use-after-free scenario. This occurs when a power management (PM) interrupt triggers just before the device-specific driver (e.g., qat_4xxx.ko) is unloaded, while the core driver (intel_qat.ko) remains loaded.

Since the driver uses a shared workqueue (qat_misc_wq) across all devices and owned by intel_qat.ko, a deferred routine from the device-specific driver may still be pending in the queue. If this routine executes after the driver is unloaded, it can dereference freed memory, resulting in a page fault and kernel crash like the following:

BUG: unable to handle page fault for address: ffa000002e50a01c
#PF: supervisor read access in kernel mode
RIP: 0010:pm_bh_handler+0x1d2/0x250 [intel_qat]
Call Trace:
  pm_bh_handler+0x1d2/0x250 [intel_qat]
  process_one_work+0x171/0x340
  worker_thread+0x277/0x3a0
  kthread+0xf0/0x120
  ret_from_fork+0x2d/0x50

To prevent this, flush the misc workqueue during device shutdown to ensure that all pending work items are completed before the driver is unloaded.

Note: This approach may slightly increase shutdown latency if the workqueue contains jobs from other devices, but it ensures correctness and stability.

CVSS Base Scores

version 3.1