{"id":"CVE-2025-40223","state":"PUBLISHED","title":"most: usb: Fix use-after-free in hdm_disconnect","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmost: usb: Fix use-after-free in hdm_disconnect\n\nhdm_disconnect() calls most_deregister_interface(), which eventually\nunregisters the MOST interface device with device_unregister(iface->dev).\nIf that drops the last reference, the device core may call release_mdev()\nimmediately while hdm_disconnect() is still executing.\n\nThe old code also freed several mdev-owned allocations in\nhdm_disconnect() and then performed additional put_device() calls.\nDepending on refcount order, this could lead to use-after-free or\ndouble-free when release_mdev() ran (or when unregister paths also\nperformed puts).\n\nFix by moving the frees of mdev-owned allocations into release_mdev(),\nso they happen exactly once when the device is truly released, and by\ndropping the extra put_device() calls in hdm_disconnect() that are\nredundant after device_unregister() and most_deregister_interface().\n\nThis addresses the KASAN slab-use-after-free reported by syzbot in\nhdm_disconnect(). See report and stack traces in the bug link below.","publishedAt":"2025-12-04T15:31:15.158Z","updatedAt":"2026-05-11T21:45:10.518Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"97a6f772f36b7f52bcfa56a581bbd2470cffe23d","status":"affected","lessThan":"5b5c478f09b1b35e7fe6fc9a1786c9bf6030e831","versionType":"git"},{"version":"97a6f772f36b7f52bcfa56a581bbd2470cffe23d","status":"affected","lessThan":"578eb18cd111addec94c43f61cd4b4429e454809","versionType":"git"},{"version":"97a6f772f36b7f52bcfa56a581bbd2470cffe23d","status":"affected","lessThan":"33daf469f5294b9d07c4fc98216cace9f4f34cc6","versionType":"git"},{"version":"97a6f772f36b7f52bcfa56a581bbd2470cffe23d","status":"affected","lessThan":"72427dc6f87523995f4e6ae35a948bb2992cabce","versionType":"git"},{"version":"97a6f772f36b7f52bcfa56a581bbd2470cffe23d","status":"affected","lessThan":"f93a84ffb884d761a9d4e869ba29c238711e81f1","versionType":"git"},{"version":"97a6f772f36b7f52bcfa56a581bbd2470cffe23d","status":"affected","lessThan":"3a3b8e89c7201c5b3b76ac4a4069d1adde1477d6","versionType":"git"},{"version":"97a6f772f36b7f52bcfa56a581bbd2470cffe23d","status":"affected","lessThan":"4b1270902609ef0d935ed2faa2ea6d122bd148f5","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/most/most_usb.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.9","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.9","versionType":"semver"},{"version":"5.10.246","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.196","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.158","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.115","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.56","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.17.6","status":"unaffected","lessThanOrEqual":"6.17.*","versionType":"semver"},{"version":"6.18","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/most/most_usb.c"]}],"references":["https://git.kernel.org/stable/c/5b5c478f09b1b35e7fe6fc9a1786c9bf6030e831","https://git.kernel.org/stable/c/578eb18cd111addec94c43f61cd4b4429e454809","https://git.kernel.org/stable/c/33daf469f5294b9d07c4fc98216cace9f4f34cc6","https://git.kernel.org/stable/c/72427dc6f87523995f4e6ae35a948bb2992cabce","https://git.kernel.org/stable/c/f93a84ffb884d761a9d4e869ba29c238711e81f1","https://git.kernel.org/stable/c/3a3b8e89c7201c5b3b76ac4a4069d1adde1477d6","https://git.kernel.org/stable/c/4b1270902609ef0d935ed2faa2ea6d122bd148f5"],"weaknesses":[],"ingestedAt":"2026-10-29T20:09:09.358Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/40xxx/CVE-2025-40223.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-40223","state":"PUBLISHED","datePublished":"2025-12-04T15:31:15.158Z","dateUpdated":"2026-05-11T21:45:10.518Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-04-16T07:20:57.180Z"},"containers":{"cna":{"title":"most: usb: Fix use-after-free in hdm_disconnect","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmost: usb: Fix use-after-free in hdm_disconnect\n\nhdm_disconnect() calls most_deregister_interface(), which eventually\nunregisters the MOST interface device with device_unregister(iface->dev).\nIf that drops the last reference, the device core may call release_mdev()\nimmediately while hdm_disconnect() is still executing.\n\nThe old code also freed several mdev-owned allocations in\nhdm_disconnect() and then performed additional put_device() calls.\nDepending on refcount order, this could lead to use-after-free or\ndouble-free when release_mdev() ran (or when unregister paths also\nperformed puts).\n\nFix by moving the frees of mdev-owned allocations into release_mdev(),\nso they happen exactly once when the device is truly released, and by\ndropping the extra put_device() calls in hdm_disconnect() that are\nredundant after device_unregister() and most_deregister_interface().\n\nThis addresses the KASAN slab-use-after-free reported by syzbot in\nhdm_disconnect(). See report and stack traces in the bug link below."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"97a6f772f36b7f52bcfa56a581bbd2470cffe23d","status":"affected","lessThan":"5b5c478f09b1b35e7fe6fc9a1786c9bf6030e831","versionType":"git"},{"version":"97a6f772f36b7f52bcfa56a581bbd2470cffe23d","status":"affected","lessThan":"578eb18cd111addec94c43f61cd4b4429e454809","versionType":"git"},{"version":"97a6f772f36b7f52bcfa56a581bbd2470cffe23d","status":"affected","lessThan":"33daf469f5294b9d07c4fc98216cace9f4f34cc6","versionType":"git"},{"version":"97a6f772f36b7f52bcfa56a581bbd2470cffe23d","status":"affected","lessThan":"72427dc6f87523995f4e6ae35a948bb2992cabce","versionType":"git"},{"version":"97a6f772f36b7f52bcfa56a581bbd2470cffe23d","status":"affected","lessThan":"f93a84ffb884d761a9d4e869ba29c238711e81f1","versionType":"git"},{"version":"97a6f772f36b7f52bcfa56a581bbd2470cffe23d","status":"affected","lessThan":"3a3b8e89c7201c5b3b76ac4a4069d1adde1477d6","versionType":"git"},{"version":"97a6f772f36b7f52bcfa56a581bbd2470cffe23d","status":"affected","lessThan":"4b1270902609ef0d935ed2faa2ea6d122bd148f5","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/most/most_usb.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.9","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.9","versionType":"semver"},{"version":"5.10.246","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.196","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.158","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.115","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.56","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.17.6","status":"unaffected","lessThanOrEqual":"6.17.*","versionType":"semver"},{"version":"6.18","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/most/most_usb.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/5b5c478f09b1b35e7fe6fc9a1786c9bf6030e831"},{"url":"https://git.kernel.org/stable/c/578eb18cd111addec94c43f61cd4b4429e454809"},{"url":"https://git.kernel.org/stable/c/33daf469f5294b9d07c4fc98216cace9f4f34cc6"},{"url":"https://git.kernel.org/stable/c/72427dc6f87523995f4e6ae35a948bb2992cabce"},{"url":"https://git.kernel.org/stable/c/f93a84ffb884d761a9d4e869ba29c238711e81f1"},{"url":"https://git.kernel.org/stable/c/3a3b8e89c7201c5b3b76ac4a4069d1adde1477d6"},{"url":"https://git.kernel.org/stable/c/4b1270902609ef0d935ed2faa2ea6d122bd148f5"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T21:45:10.518Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"5.10.246"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"5.15.196"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.1.158"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.6.115"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.12.56"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.17.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.18"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}