{"id":"CVE-2026-74334","state":"PUBLISHED","title":"RDMA/nldev: Fix locking when accessing mr->pd","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/nldev: Fix locking when accessing mr->pd\n\nSashiko points out that, due to rereg_mr, the PD is actually variable and\nall the touches in nldev are racy.\n\nUse mr->device instead of mr->pd->device.\n\nGetting the PD restrack ID is more tricky. To avoid disturbing all the\nhappy paths, add an rdma_restrack_sync() operation which is sort of like\nflush_workqueue() or synchronize_irq(): after it returns, all the old\nnldev touches to the mr are gone and everything sees the new PD. This\nmakes it safe to reach into the PD pointer.","publishedAt":"2026-08-15T05:58:26.455Z","updatedAt":"2026-10-16T18:55:33.821Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"da5c8507821573b8ed6e3f47e009f273493ffaf7","status":"affected","lessThan":"845c6b355226195dad1f26b300c4830f57034e8b","versionType":"git"},{"version":"da5c8507821573b8ed6e3f47e009f273493ffaf7","status":"affected","lessThan":"7a0cbb5721a1da81e902d73b6049f85ca8f3fc0a","versionType":"git"},{"version":"da5c8507821573b8ed6e3f47e009f273493ffaf7","status":"affected","lessThan":"05e26f34597e9c38bb5b340d86b179b23673869f","versionType":"git"},{"version":"da5c8507821573b8ed6e3f47e009f273493ffaf7","status":"affected","lessThan":"a07cba1296aaa81bf9b914486ca957aaff196247","versionType":"git"},{"version":"da5c8507821573b8ed6e3f47e009f273493ffaf7","status":"affected","lessThan":"1a132ee4e655288d9a0937ea5109a0d038431ae9","versionType":"git"},{"version":"da5c8507821573b8ed6e3f47e009f273493ffaf7","status":"affected","lessThan":"50d5c02ab8e62325548bd3a6e6b758a9dcd6e7c3","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/infiniband/core/nldev.c","drivers/infiniband/core/restrack.c","drivers/infiniband/core/restrack.h","drivers/infiniband/core/uverbs_cmd.c","include/rdma/ib_verbs.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.18","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.18","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.52","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/infiniband/core/nldev.c","drivers/infiniband/core/restrack.c","drivers/infiniband/core/restrack.h","drivers/infiniband/core/uverbs_cmd.c","include/rdma/ib_verbs.h"]}],"references":["https://git.kernel.org/stable/c/845c6b355226195dad1f26b300c4830f57034e8b","https://git.kernel.org/stable/c/7a0cbb5721a1da81e902d73b6049f85ca8f3fc0a","https://git.kernel.org/stable/c/05e26f34597e9c38bb5b340d86b179b23673869f","https://git.kernel.org/stable/c/a07cba1296aaa81bf9b914486ca957aaff196247","https://git.kernel.org/stable/c/1a132ee4e655288d9a0937ea5109a0d038431ae9","https://git.kernel.org/stable/c/50d5c02ab8e62325548bd3a6e6b758a9dcd6e7c3"],"weaknesses":[],"ingestedAt":"2026-10-29T20:12:58.252Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/74xxx/CVE-2026-74334.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-74334","state":"PUBLISHED","datePublished":"2026-08-15T05:58:26.455Z","dateUpdated":"2026-10-16T18:55:33.821Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-15T05:44:03.885Z"},"containers":{"cna":{"title":"RDMA/nldev: Fix locking when accessing mr->pd","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nRDMA/nldev: Fix locking when accessing mr->pd\n\nSashiko points out that, due to rereg_mr, the PD is actually variable and\nall the touches in nldev are racy.\n\nUse mr->device instead of mr->pd->device.\n\nGetting the PD restrack ID is more tricky. To avoid disturbing all the\nhappy paths, add an rdma_restrack_sync() operation which is sort of like\nflush_workqueue() or synchronize_irq(): after it returns, all the old\nnldev touches to the mr are gone and everything sees the new PD. This\nmakes it safe to reach into the PD pointer."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"da5c8507821573b8ed6e3f47e009f273493ffaf7","status":"affected","lessThan":"845c6b355226195dad1f26b300c4830f57034e8b","versionType":"git"},{"version":"da5c8507821573b8ed6e3f47e009f273493ffaf7","status":"affected","lessThan":"7a0cbb5721a1da81e902d73b6049f85ca8f3fc0a","versionType":"git"},{"version":"da5c8507821573b8ed6e3f47e009f273493ffaf7","status":"affected","lessThan":"05e26f34597e9c38bb5b340d86b179b23673869f","versionType":"git"},{"version":"da5c8507821573b8ed6e3f47e009f273493ffaf7","status":"affected","lessThan":"a07cba1296aaa81bf9b914486ca957aaff196247","versionType":"git"},{"version":"da5c8507821573b8ed6e3f47e009f273493ffaf7","status":"affected","lessThan":"1a132ee4e655288d9a0937ea5109a0d038431ae9","versionType":"git"},{"version":"da5c8507821573b8ed6e3f47e009f273493ffaf7","status":"affected","lessThan":"50d5c02ab8e62325548bd3a6e6b758a9dcd6e7c3","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/infiniband/core/nldev.c","drivers/infiniband/core/restrack.c","drivers/infiniband/core/restrack.h","drivers/infiniband/core/uverbs_cmd.c","include/rdma/ib_verbs.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.18","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.18","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.52","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/infiniband/core/nldev.c","drivers/infiniband/core/restrack.c","drivers/infiniband/core/restrack.h","drivers/infiniband/core/uverbs_cmd.c","include/rdma/ib_verbs.h"]}],"references":[{"url":"https://git.kernel.org/stable/c/845c6b355226195dad1f26b300c4830f57034e8b"},{"url":"https://git.kernel.org/stable/c/7a0cbb5721a1da81e902d73b6049f85ca8f3fc0a"},{"url":"https://git.kernel.org/stable/c/05e26f34597e9c38bb5b340d86b179b23673869f"},{"url":"https://git.kernel.org/stable/c/a07cba1296aaa81bf9b914486ca957aaff196247"},{"url":"https://git.kernel.org/stable/c/1a132ee4e655288d9a0937ea5109a0d038431ae9"},{"url":"https://git.kernel.org/stable/c/50d5c02ab8e62325548bd3a6e6b758a9dcd6e7c3"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The bug is reached via local NETLINK_RDMA nldev MR resource dumps and concurrent IB_USER_VERBS_CMD_REREG_MR ioctl on /dev/infiniband/uverbs; it is not triggered by remote RDMA/InfiniBand/RoCE network traffic.\nAC:L - An attacker controls both race sides by spawning threads that hammer rereg_mr with IB_MR_REREG_PD and nldev RES_MR_GET dumps, optionally deallocating the old PD; no timing or layout conditions outside attacker control are required.\nPR:L - Exploitation needs only local uverbs access (device nodes default 0666) plus NETLINK_RDMA dumps; CAP_NET_ADMIN for netlink send is obtainable by unprivileged users via user namespaces, not real init-namespace root.\nUI:N - No victim interaction is required; the attacker triggers both the rereg_mr PD change and the concurrent nldev MR dump from their own process.\nS:U - Impact is kernel heap corruption and privilege escalation within the host kernel security boundary, not a VM escape, IOMMU bypass, or cross-authority sandbox breakout.\nC:H - Concurrent rereg_mr can free the old ib_pd while nldev still dereferences mr->pd for device and res.id, creating a use-after-free that enables arbitrary kernel memory disclosure via controlled reuse of freed slab objects.\nI:H - The ib_pd UAF is exploitable for heap grooming and arbitrary kernel write or control-flow hijack, not merely a bounded data corruption or guaranteed crash.\nA:H - The race reliably causes kernel oops or panic from dereferencing a freed ib_pd during nldev dumps, and UAF exploitation can additionally crash or hang the system during heap manipulation."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-09-14T11:58:43.928Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.18","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.18","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.18","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.18","versionEndExcluding":"6.18.52"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.18","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.18","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-74334","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T18:53:49.608601Z"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-16T18:55:33.821Z"}}]}}}