CVE-2025-40211

CVE-2025-40211 is a security vulnerability that is still awaiting full analysis and scoring. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: ACPI: video: Fix use-after-free in acpi_video_switch_brightness() The switch_brightness_work delayed work accesses device->brightness and device->backlight, freed by acpi_video_dev_unregister_backlight() during device removal. If the work executes after acpi_video_bus_unregister_backlight() frees these resources, it causes a use-after-free when acpi_video_switch_brightness() dereferences device->brightness or device->backlight. Fix this by calling cancel_delayed_work_sync() for each device's switch_brightness_work in acpi_video_bus_remove_notify_handler() after removing the notify handler that queues the work. This ensures the work completes before the memory is freed. [ rjw: Changelog edit ]

Frequently asked questions

What is CVE-2025-40211?
In the Linux kernel, the following vulnerability has been resolved: ACPI: video: Fix use-after-free in acpi_video_switch_brightness() The switch_brightness_work delayed work accesses device->brightness and device->backlight, freed by acpi_video_dev_unregister_backlight() during device removal. If the work executes after acpi_video_bus_unregister_backlight() frees these resources, it causes a use-after-free when acpi_video_switch_brightness() dereferences device->brightness or device->backlight. Fix this by calling cancel_delayed_work_sync() for each device's switch_brightness_work in acpi_video_bus_remove_notify_handler() after removing the notify handler that queues the work. This ensures the work completes before the memory is freed. [ rjw: Changelog edit ]
Is CVE-2025-40211 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2025-40211?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-40211 have an EU (EUVD) identifier?
Yes. CVE-2025-40211 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-198436.
When was CVE-2025-40211 published?
CVE-2025-40211 was published on 2025-11-21 and last updated on 2026-06-17.

References