{"id":"CVE-2026-72073","state":"PUBLISHED","title":"mmc: vub300: fix use-after-free on probe failure","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmmc: vub300: fix use-after-free on probe failure\n\nThe vub300 driver lifetime-manages its controller state using\nvub300->kref, with vub300_delete() freeing the mmc host when the last\nreference is dropped. The probe error path after the inactivity timer has\nbeen armed still bypasses that lifetime rule, however, and falls through\nto mmc_free_host() directly if mmc_add_host() fails.\n\nThe race window is between arming the inactivity timer and reaching the\nprobe error unwind after mmc_add_host() fails:\n\n        probe thread                     timer/workqueue\n        ------------                     ---------------\n        kref_init(&vub300->kref)         ref = 1\n        kref_get(&vub300->kref)          ref = 2, timer ref\n        add_timer(inactivity_timer)      fires after one second\n        |\n        |   race window\n        |<---------------------------------------------------->\n        |\n        mmc_add_host(mmc)\n                                         inactivity timer fires\n                                         vub300_queue_dead_work()\n                                           kref_get()          ref = 3\n                                           queue_work(deadwork)\n        mmc_add_host() fails\n        timer_delete_sync()\n        mmc_free_host(mmc)\n          frees vub300\n                                         deadwork runs\n                                           use-after-free\n\nThe inactivity timeout is one second, so this would require\nmmc_add_host() to both fail and take more than one second to do so. This\nis unlikely to happen in practice, but the error path is still wrong.\n\ntimer_delete_sync() only waits for the timer callback itself. It does\nnot flush deadwork that the callback may already have queued. As a\nresult, queued deadwork can still hold a kref while the probe error path\ndirectly frees the backing mmc host, including the vub300 storage.\n\nFix this by using the same lifetime mechanism as disconnect. Clear\nvub300->interface so that the timer callback and any queued deadwork\nreturn early and drop their references, then drop the initial probe\nreference and return without falling through to err_free_host.","publishedAt":"2026-08-15T05:52:24.676Z","updatedAt":"2026-10-21T12:44:20.898Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"0613ad2401f88bdeae5594c30afe318e93b14676","status":"affected","lessThan":"face65f80c6946c631ca3490b4ebd2c016a4fd2c","versionType":"git"},{"version":"0613ad2401f88bdeae5594c30afe318e93b14676","status":"affected","lessThan":"6c66653dac9b25272d5fd4ed42a34aa5249e16df","versionType":"git"},{"version":"0613ad2401f88bdeae5594c30afe318e93b14676","status":"affected","lessThan":"5b82af744e06cd741938c3da54fdbe564a7e52d9","versionType":"git"},{"version":"0613ad2401f88bdeae5594c30afe318e93b14676","status":"affected","lessThan":"618cf6b139503ec18ef93ffd663396aaf99b763a","versionType":"git"},{"version":"0613ad2401f88bdeae5594c30afe318e93b14676","status":"affected","lessThan":"a3b5f242997a3be7404112fd48784881560aea57","versionType":"git"},{"version":"41ed46bdbd2878cd6567abe0974a445f8b1b8ec8","status":"affected","versionType":"git"},{"version":"25f05d762ca5e1c685002a53dd44f68e78ca3feb","status":"affected","versionType":"git"},{"version":"a46e681151bbdacdf6b89ee8c4e5bad0555142bb","status":"affected","versionType":"git"},{"version":"3b29f8769d32016b2d89183db4d80c7a71b7e35e","status":"affected","versionType":"git"},{"version":"3049a3b927a40d89d4582ff1033cd7953be773c7","status":"affected","versionType":"git"},{"version":"afc898019e7bf18c5eb7a0ac19852fcb1b341b3c","status":"affected","versionType":"git"},{"version":"c9e85979b59cb86f0a15defa8199d740e2b36b90","status":"affected","versionType":"git"},{"version":"2044b2ea77945f372ef161d1bbf814e471767ff2","status":"affected","versionType":"git"},{"version":"4.9.337","status":"affected","lessThan":"4.10","versionType":"semver"},{"version":"4.14.303","status":"affected","lessThan":"4.15","versionType":"semver"},{"version":"4.19.270","status":"affected","lessThan":"4.20","versionType":"semver"},{"version":"5.4.229","status":"affected","lessThan":"5.5","versionType":"semver"},{"version":"5.10.163","status":"affected","lessThan":"5.11","versionType":"semver"},{"version":"5.15.86","status":"affected","lessThan":"5.16","versionType":"semver"},{"version":"6.0.16","status":"affected","lessThan":"6.1","versionType":"semver"},{"version":"6.1.2","status":"affected","lessThan":"6.2","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/mmc/host/vub300.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.2","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.2","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.114","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.42","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/mmc/host/vub300.c"]}],"references":["https://git.kernel.org/stable/c/face65f80c6946c631ca3490b4ebd2c016a4fd2c","https://git.kernel.org/stable/c/6c66653dac9b25272d5fd4ed42a34aa5249e16df","https://git.kernel.org/stable/c/5b82af744e06cd741938c3da54fdbe564a7e52d9","https://git.kernel.org/stable/c/618cf6b139503ec18ef93ffd663396aaf99b763a","https://git.kernel.org/stable/c/a3b5f242997a3be7404112fd48784881560aea57"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/72xxx/CVE-2026-72073.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-72073","state":"PUBLISHED","datePublished":"2026-08-15T05:52:24.676Z","dateUpdated":"2026-10-21T12:44:20.898Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-09T03:40:39.904Z"},"containers":{"cna":{"title":"mmc: vub300: fix use-after-free on probe failure","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nmmc: vub300: fix use-after-free on probe failure\n\nThe vub300 driver lifetime-manages its controller state using\nvub300->kref, with vub300_delete() freeing the mmc host when the last\nreference is dropped. The probe error path after the inactivity timer has\nbeen armed still bypasses that lifetime rule, however, and falls through\nto mmc_free_host() directly if mmc_add_host() fails.\n\nThe race window is between arming the inactivity timer and reaching the\nprobe error unwind after mmc_add_host() fails:\n\n        probe thread                     timer/workqueue\n        ------------                     ---------------\n        kref_init(&vub300->kref)         ref = 1\n        kref_get(&vub300->kref)          ref = 2, timer ref\n        add_timer(inactivity_timer)      fires after one second\n        |\n        |   race window\n        |<---------------------------------------------------->\n        |\n        mmc_add_host(mmc)\n                                         inactivity timer fires\n                                         vub300_queue_dead_work()\n                                           kref_get()          ref = 3\n                                           queue_work(deadwork)\n        mmc_add_host() fails\n        timer_delete_sync()\n        mmc_free_host(mmc)\n          frees vub300\n                                         deadwork runs\n                                           use-after-free\n\nThe inactivity timeout is one second, so this would require\nmmc_add_host() to both fail and take more than one second to do so. This\nis unlikely to happen in practice, but the error path is still wrong.\n\ntimer_delete_sync() only waits for the timer callback itself. It does\nnot flush deadwork that the callback may already have queued. As a\nresult, queued deadwork can still hold a kref while the probe error path\ndirectly frees the backing mmc host, including the vub300 storage.\n\nFix this by using the same lifetime mechanism as disconnect. Clear\nvub300->interface so that the timer callback and any queued deadwork\nreturn early and drop their references, then drop the initial probe\nreference and return without falling through to err_free_host."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"0613ad2401f88bdeae5594c30afe318e93b14676","status":"affected","lessThan":"face65f80c6946c631ca3490b4ebd2c016a4fd2c","versionType":"git"},{"version":"0613ad2401f88bdeae5594c30afe318e93b14676","status":"affected","lessThan":"6c66653dac9b25272d5fd4ed42a34aa5249e16df","versionType":"git"},{"version":"0613ad2401f88bdeae5594c30afe318e93b14676","status":"affected","lessThan":"5b82af744e06cd741938c3da54fdbe564a7e52d9","versionType":"git"},{"version":"0613ad2401f88bdeae5594c30afe318e93b14676","status":"affected","lessThan":"618cf6b139503ec18ef93ffd663396aaf99b763a","versionType":"git"},{"version":"0613ad2401f88bdeae5594c30afe318e93b14676","status":"affected","lessThan":"a3b5f242997a3be7404112fd48784881560aea57","versionType":"git"},{"version":"41ed46bdbd2878cd6567abe0974a445f8b1b8ec8","status":"affected","versionType":"git"},{"version":"25f05d762ca5e1c685002a53dd44f68e78ca3feb","status":"affected","versionType":"git"},{"version":"a46e681151bbdacdf6b89ee8c4e5bad0555142bb","status":"affected","versionType":"git"},{"version":"3b29f8769d32016b2d89183db4d80c7a71b7e35e","status":"affected","versionType":"git"},{"version":"3049a3b927a40d89d4582ff1033cd7953be773c7","status":"affected","versionType":"git"},{"version":"afc898019e7bf18c5eb7a0ac19852fcb1b341b3c","status":"affected","versionType":"git"},{"version":"c9e85979b59cb86f0a15defa8199d740e2b36b90","status":"affected","versionType":"git"},{"version":"2044b2ea77945f372ef161d1bbf814e471767ff2","status":"affected","versionType":"git"},{"version":"4.9.337","status":"affected","lessThan":"4.10","versionType":"semver"},{"version":"4.14.303","status":"affected","lessThan":"4.15","versionType":"semver"},{"version":"4.19.270","status":"affected","lessThan":"4.20","versionType":"semver"},{"version":"5.4.229","status":"affected","lessThan":"5.5","versionType":"semver"},{"version":"5.10.163","status":"affected","lessThan":"5.11","versionType":"semver"},{"version":"5.15.86","status":"affected","lessThan":"5.16","versionType":"semver"},{"version":"6.0.16","status":"affected","lessThan":"6.1","versionType":"semver"},{"version":"6.1.2","status":"affected","lessThan":"6.2","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/mmc/host/vub300.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.2","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.2","versionType":"semver"},{"version":"6.6.160","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.114","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.42","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.5","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/mmc/host/vub300.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/face65f80c6946c631ca3490b4ebd2c016a4fd2c"},{"url":"https://git.kernel.org/stable/c/6c66653dac9b25272d5fd4ed42a34aa5249e16df"},{"url":"https://git.kernel.org/stable/c/5b82af744e06cd741938c3da54fdbe564a7e52d9"},{"url":"https://git.kernel.org/stable/c/618cf6b139503ec18ef93ffd663396aaf99b763a"},{"url":"https://git.kernel.org/stable/c/a3b5f242997a3be7404112fd48784881560aea57"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-21T12:44:20.898Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"6.6.160"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"6.12.114"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"6.18.42"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"7.2"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.9.337"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14.303"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19.270"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4.229"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10.163"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15.86"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.0.16"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}