{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-68372","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2025-12-16T14:48:05.310Z","datePublished":"2025-12-24T10:33:02.679Z","dateUpdated":"2026-05-11T21:51:55.998Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-05-11T21:51:55.998Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnbd: defer config put in recv_work\n\nThere is one uaf issue in recv_work when running NBD_CLEAR_SOCK and\nNBD_CMD_RECONFIGURE:\n  nbd_genl_connect     // conf_ref=2 (connect and recv_work A)\n  nbd_open\t       // conf_ref=3\n  recv_work A done     // conf_ref=2\n  NBD_CLEAR_SOCK       // conf_ref=1\n  nbd_genl_reconfigure // conf_ref=2 (trigger recv_work B)\n  close nbd\t       // conf_ref=1\n  recv_work B\n    config_put         // conf_ref=0\n    atomic_dec(&config->recv_threads); -> UAF\n\nOr only running NBD_CLEAR_SOCK:\n  nbd_genl_connect   // conf_ref=2\n  nbd_open \t     // conf_ref=3\n  NBD_CLEAR_SOCK     // conf_ref=2\n  close nbd\n    nbd_release\n      config_put     // conf_ref=1\n  recv_work\n    config_put \t     // conf_ref=0\n    atomic_dec(&config->recv_threads); -> UAF\n\nCommit 87aac3a80af5 (\"nbd: call nbd_config_put() before notifying the\nwaiter\") moved nbd_config_put() to run before waking up the waiter in\nrecv_work, in order to ensure that nbd_start_device_ioctl() would not\nbe woken up while nbd->task_recv was still uncleared.\n\nHowever, in nbd_start_device_ioctl(), after being woken up it explicitly\ncalls flush_workqueue() to make sure all current works are finished.\nTherefore, there is no need to move the config put ahead of the wakeup.\n\nMove nbd_config_put() to the end of recv_work, so that the reference is\nheld for the whole lifetime of the worker thread. This makes sure the\nconfig cannot be freed while recv_work is still running, even if clear\n+ reconfigure interleave.\n\nIn addition, we don't need to worry about recv_work dropping the last\nnbd_put (which causes deadlock):\n\npath A (netlink with NBD_CFLAG_DESTROY_ON_DISCONNECT):\n  connect  // nbd_refs=1 (trigger recv_work)\n  open nbd // nbd_refs=2\n  NBD_CLEAR_SOCK\n  close nbd\n    nbd_release\n      nbd_disconnect_and_put\n        flush_workqueue // recv_work done\n      nbd_config_put\n        nbd_put // nbd_refs=1\n      nbd_put // nbd_refs=0\n        queue_work\n\npath B (netlink without NBD_CFLAG_DESTROY_ON_DISCONNECT):\n  connect  // nbd_refs=2 (trigger recv_work)\n  open nbd // nbd_refs=3\n  NBD_CLEAR_SOCK // conf_refs=2\n  close nbd\n    nbd_release\n      nbd_config_put // conf_refs=1\n      nbd_put // nbd_refs=2\n  recv_work done // conf_refs=0, nbd_refs=1\n  rmmod // nbd_refs=0\n\nDepends-on: e2daec488c57 (\"nbd: Fix hungtask when nbd_config_put\")"}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/block/nbd.c"],"versions":[{"version":"87aac3a80af5cbad93e63250e8a1e19095ba0d30","lessThan":"198aa230a6f8c1f6af7ed26b29180749c3e79e4d","status":"affected","versionType":"git"},{"version":"87aac3a80af5cbad93e63250e8a1e19095ba0d30","lessThan":"d3ba312675911ff9e3fefefd551751e153a9f0a9","status":"affected","versionType":"git"},{"version":"87aac3a80af5cbad93e63250e8a1e19095ba0d30","lessThan":"3692884bd6187d89d41eef81e5a9724519fd01c1","status":"affected","versionType":"git"},{"version":"87aac3a80af5cbad93e63250e8a1e19095ba0d30","lessThan":"1ba2ced2bbdf7e64a30c3e88c70ea8bc208d1509","status":"affected","versionType":"git"},{"version":"87aac3a80af5cbad93e63250e8a1e19095ba0d30","lessThan":"6b69593f72e1bfba6ca47ca8d9b619341fded7d6","status":"affected","versionType":"git"},{"version":"87aac3a80af5cbad93e63250e8a1e19095ba0d30","lessThan":"443a1721806b6ff6303b5229e9811d68172d622f","status":"affected","versionType":"git"},{"version":"87aac3a80af5cbad93e63250e8a1e19095ba0d30","lessThan":"742012f6bf29553fdc460bf646a58df3a7b43d01","status":"affected","versionType":"git"},{"version":"87aac3a80af5cbad93e63250e8a1e19095ba0d30","lessThan":"9517b82d8d422d426a988b213fdd45c6b417b86d","status":"affected","versionType":"git"},{"version":"0a4e383fc3aa6540f804c4fd1184a96ae5de6ef8","status":"affected","versionType":"git"},{"version":"2ef6f4bd60411934e3fc2715442c2afe70f84bf3","status":"affected","versionType":"git"},{"version":"742fd49cf811ca164489e339b862e3fb8e240a73","status":"affected","versionType":"git"},{"version":"14df8724aeeef338172e2a2d6efadc989921ca0f","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/block/nbd.c"],"versions":[{"version":"5.10","status":"affected"},{"version":"0","lessThan":"5.10","status":"unaffected","versionType":"semver"},{"version":"5.10.248","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.198","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.160","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.120","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.63","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.17.13","lessThanOrEqual":"6.17.*","status":"unaffected","versionType":"semver"},{"version":"6.18.2","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"6.19","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":"5.10","versionEndExcluding":"5.10.248"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"5.15.198"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.1.160"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.6.120"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.12.63"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.17.13"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.18.2"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10","versionEndExcluding":"6.19"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14.204"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.19.155"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4.75"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9.5"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/198aa230a6f8c1f6af7ed26b29180749c3e79e4d"},{"url":"https://git.kernel.org/stable/c/d3ba312675911ff9e3fefefd551751e153a9f0a9"},{"url":"https://git.kernel.org/stable/c/3692884bd6187d89d41eef81e5a9724519fd01c1"},{"url":"https://git.kernel.org/stable/c/1ba2ced2bbdf7e64a30c3e88c70ea8bc208d1509"},{"url":"https://git.kernel.org/stable/c/6b69593f72e1bfba6ca47ca8d9b619341fded7d6"},{"url":"https://git.kernel.org/stable/c/443a1721806b6ff6303b5229e9811d68172d622f"},{"url":"https://git.kernel.org/stable/c/742012f6bf29553fdc460bf646a58df3a7b43d01"},{"url":"https://git.kernel.org/stable/c/9517b82d8d422d426a988b213fdd45c6b417b86d"}],"title":"nbd: defer config put in recv_work","x_generator":{"engine":"bippy-1.2.0"}}}}