CVE-2025-40223
In the Linux kernel, the following vulnerability has been resolved: most: usb: Fix use-after-free in hdm_disconnect hdm_disconnect() calls most_deregister_interface(), which eventually unregisters the MOST interface device with…
Does this matter?
Not yet scored. NVD analysis is pending; check back once CVSS and EPSS values are published.
Description
In the Linux kernel, the following vulnerability has been resolved: most: usb: Fix use-after-free in hdm_disconnect hdm_disconnect() calls most_deregister_interface(), which eventually unregisters the MOST interface device with device_unregister(iface->dev). If that drops the last reference, the device core may call release_mdev() immediately while hdm_disconnect() is still executing. The old code also freed several mdev-owned allocations in hdm_disconnect() and then performed additional put_device() calls. Depending on refcount order, this could lead to use-after-free or double-free when release_mdev() ran (or when unregister paths also performed puts). Fix by moving the frees of mdev-owned allocations into release_mdev(), so they happen exactly once when the device is truly released, and by dropping the extra put_device() calls in hdm_disconnect() that are redundant after device_unregister() and most_deregister_interface(). This addresses the KASAN slab-use-after-free reported by syzbot in hdm_disconnect(). See report and stack traces in the bug link below.
- CVSS
- Not yet scored
- EPSS
- 0.21% probability · 11th percentile
- CISA KEV
- Not listed
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/33daf469f5294b9d07c4fc98216cace9f4f34cc6
- https://git.kernel.org/stable/c/3a3b8e89c7201c5b3b76ac4a4069d1adde1477d6
- https://git.kernel.org/stable/c/4b1270902609ef0d935ed2faa2ea6d122bd148f5
- https://git.kernel.org/stable/c/578eb18cd111addec94c43f61cd4b4429e454809
- https://git.kernel.org/stable/c/5b5c478f09b1b35e7fe6fc9a1786c9bf6030e831
- https://git.kernel.org/stable/c/72427dc6f87523995f4e6ae35a948bb2992cabce
- https://git.kernel.org/stable/c/f93a84ffb884d761a9d4e869ba29c238711e81f1
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.