CVE-2026-43447: iavf: fix PTP use-after-free during reset

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-08 · updated 2026-06-17
Weakness: CWE-416

Description

In the Linux kernel, the following vulnerability has been resolved: iavf: fix PTP use-after-free during reset Commit 7c01dbfc8a1c5f ("iavf: periodically cache PHC time") introduced a worker to cache PHC time, but failed to stop it during reset or disable. This creates a race condition where `iavf_reset_task()` or `iavf_disable_vf()` free adapter resources (AQ) while the worker is still running. If the worker triggers `iavf_queue_ptp_cmd()` during teardown, it accesses freed memory/locks, leading to a crash. Fix this by calling `iavf_ptp_release()` before tearing down the adapter. This ensures `ptp_clock_unregister()` synchronously cancels the worker and cleans up the chardev before the backing resources are destroyed.

Affected products

Linux kernel: from 6.15 before 6.18.19; from 6.19 before 6.19.9; 7.0-rc1, 7.0-rc2, 7.0-rc3 — fixed in 6.18.19, 6.19.9

How to fix

Upgrade to a fixed version: Linux kernel 6.18.19, 6.19.9. Check the vendor advisory for mitigations.

References

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