{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-63905","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-07-19T07:54:57.020Z","datePublished":"2026-07-19T14:55:12.270Z","dateUpdated":"2026-07-19T14:55:12.270Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-07-19T14:55:12.270Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nusbip: vudc: Fix use after free bug in vudc_remove due to race condition\n\nThis patch follows up Zheng Wang's 2023 report of a use-after-free in\nvudc_remove(). The original thread stalled on Shuah Khan's request for\nruntime testing of the unplug/unbind path. This patch supplies that\ntesting and keeps Zheng's original fix shape.\n\nIn vudc_probe(), v_init_timer() binds udc->tr_timer.timer to v_timer().\nusbip_sockfd_store() starts the timer via v_start_timer()/v_kick_timer().\nvudc_remove() can then free the containing struct vudc while the timer is\nstill pending or executing.\n\nKASAN confirms the race on an unpatched x86_64 QEMU guest with\nCONFIG_KASAN=y, CONFIG_USBIP_VUDC=y, CONFIG_USB_ZERO=y, and a tight loop\nthat repeatedly writes a socket fd to usbip_sockfd, closes the socket\npair, and unbinds/rebinds usbip-vudc.0:\n\n  BUG: KASAN: slab-use-after-free in __run_timer_base.part.0+0x8ba/0x8e0\n  Write of size 8 at addr ffff888001b80740 by task trigger_and_unb/239\n  Allocated by task 239:\n    vudc_probe+0x4d/0xaa0\n  Freed by task 239:\n    kfree+0x18f/0x520\n    device_release_driver_internal+0x388/0x540\n    unbind_store+0xd9/0x100\n\nThis lands in the timer core rather than v_timer() itself because the\nembedded timer_list is being walked after its containing struct vudc has\nalready been freed. The underlying lifetime bug is the same one Zheng\nreported.\n\nWith v_stop_timer() called from vudc_remove() and the timer deleted\nsynchronously, the same harness completed 5000 bind/unbind iterations\nwith no KASAN report."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/usb/usbip/vudc_dev.c","drivers/usb/usbip/vudc_transfer.c"],"versions":[{"version":"b6a0ca11186759ad7045d68a5447b1e89f658384","lessThan":"61704e5cf9cd7464b510eb606e7e2978b1160a64","status":"affected","versionType":"git"},{"version":"b6a0ca11186759ad7045d68a5447b1e89f658384","lessThan":"dcc1c90b28b28b7c493547506297e78653f81952","status":"affected","versionType":"git"},{"version":"b6a0ca11186759ad7045d68a5447b1e89f658384","lessThan":"1036ac6148995feaf486014d32bf26bf993c06a9","status":"affected","versionType":"git"},{"version":"b6a0ca11186759ad7045d68a5447b1e89f658384","lessThan":"a0638db2340ee053ab0450656a763fd111475e54","status":"affected","versionType":"git"},{"version":"b6a0ca11186759ad7045d68a5447b1e89f658384","lessThan":"d07ed707467ce05ea9c03412d0c5ee9d0fe386a6","status":"affected","versionType":"git"},{"version":"b6a0ca11186759ad7045d68a5447b1e89f658384","lessThan":"88d459e5b5a46da1ef9fd6f52d9439343edeec88","status":"affected","versionType":"git"},{"version":"b6a0ca11186759ad7045d68a5447b1e89f658384","lessThan":"207bf80362df3fce8ebc9723351dcb1bc6d9ed0f","status":"affected","versionType":"git"},{"version":"b6a0ca11186759ad7045d68a5447b1e89f658384","lessThan":"d96209626a29ea64666be98c30b30ac82e5f1be6","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/usb/usbip/vudc_dev.c","drivers/usb/usbip/vudc_transfer.c"],"versions":[{"version":"4.7","status":"affected"},{"version":"0","lessThan":"4.7","status":"unaffected","versionType":"semver"},{"version":"5.10.259","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.210","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.176","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.143","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.93","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.35","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.0.12","lessThanOrEqual":"7.0.*","status":"unaffected","versionType":"semver"},{"version":"7.1","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.7","versionEndExcluding":"5.10.259"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.7","versionEndExcluding":"5.15.210"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.7","versionEndExcluding":"6.1.176"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.7","versionEndExcluding":"6.6.143"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.7","versionEndExcluding":"6.12.93"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.7","versionEndExcluding":"6.18.35"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.7","versionEndExcluding":"7.0.12"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.7","versionEndExcluding":"7.1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/61704e5cf9cd7464b510eb606e7e2978b1160a64"},{"url":"https://git.kernel.org/stable/c/dcc1c90b28b28b7c493547506297e78653f81952"},{"url":"https://git.kernel.org/stable/c/1036ac6148995feaf486014d32bf26bf993c06a9"},{"url":"https://git.kernel.org/stable/c/a0638db2340ee053ab0450656a763fd111475e54"},{"url":"https://git.kernel.org/stable/c/d07ed707467ce05ea9c03412d0c5ee9d0fe386a6"},{"url":"https://git.kernel.org/stable/c/88d459e5b5a46da1ef9fd6f52d9439343edeec88"},{"url":"https://git.kernel.org/stable/c/207bf80362df3fce8ebc9723351dcb1bc6d9ed0f"},{"url":"https://git.kernel.org/stable/c/d96209626a29ea64666be98c30b30ac82e5f1be6"}],"title":"usbip: vudc: Fix use after free bug in vudc_remove due to race condition","x_generator":{"engine":"bippy-1.2.0"}}}}