{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-74365", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.888Z", "datePublished": "2026-08-15T05:58:47.594Z", "dateUpdated": "2026-08-17T05:46:24.251Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T05:46:24.251Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnvdimm/btt: Handle preemption in BTT lane acquisition\n\nBTT lanes serialize access to per-lane metadata and workspace state\nduring BTT I/O. The btt-check unit test reports data mismatches during\nBTT writes due to a race in lane acquisition that can lead to silent\ndata corruption.\n\nThe existing lane model uses a spinlock together with a per-CPU\nrecursion count. That recursion model stopped being valid after BTT\nlanes became preemptible: another task can run on the same CPU,\nobserve a non-zero recursion count, bypass locking, and use the same\nlane concurrently.\n\nBTT lanes are also held across arena_write_bytes() calls. That path\nreaches nsio_rw_bytes(), which flushes writes with nvdimm_flush().\nSome provider flush callbacks can sleep, making a spinlock the wrong\nprimitive for the lane lifetime.\n\nReplace the spinlock-based recursion model with a dynamically\nallocated per-lane mutex array and take the lane lock\nunconditionally.\n\nAdd might_sleep() to catch any future atomic-context caller.\n\nFound with the ndctl unit test btt-check.sh." } ], "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:L", "baseScore": 7.3, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The flaw is reached only through local block I/O on a BTT-backed /dev/pmem* device via vfs_write/pwrite/O_DIRECT paths into btt_submit_bio->btt_write_pg/btt_read_pg->nd_region_acquire_lane; it is not in a network protocol handler.\nAC:L - After BTT lanes became preemptible, a second task on the same CPU can bypass the per-CPU recursion spinlock while the first still holds the lane across sleeping arena_write_bytes/nvdimm_flush; an attacker reliably wins by issuing concurrent writes (e.g., many threads) to the BTT block device.\nPR:L - No capability checks exist on the bio submission path; any local principal with write access to the BTT block device or a filesystem mounted on it (common for database/service accounts on PMEM servers) can trigger the race without real init-namespace root.\nUI:N - Exploitation requires only automated concurrent block writes from the attacker-controlled process and does not depend on any victim user opening files, clicking prompts, or performing other interactive actions.\nS:U - Impact is confined to corrupting BTT metadata and data within the attacker's reachable persistent-memory namespace on the same host; it does not cross VM, container, or IOMMU security boundaries to affect other security authorities.\nC:H - Unserialized lane use corrupts BTT map/log/freelist and in-memory arena->rtt/freelist state, so reads can return stale or mis-mapped sector contents (cross-LBA disclosure); the ndctl btt-check test observed data mismatches confirming readable integrity loss.\nI:H - Concurrent writers can silently corrupt on-media BTT translation tables and user data blocks, producing arbitrary persistent storage modification rather than a bounded or detectable single-field change, matching the fix commit's silent data-corruption description.\nA:L - The primary failure mode is silent corruption and subsequent I/O errors on the affected namespace rather than a kernel panic or hang, but corrupted BTT metadata can persistently degrade or deny reliable access to the volume until recovery or rebuild." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "Documentation/driver-api/nvdimm/btt.rst", "drivers/nvdimm/nd.h", "drivers/nvdimm/region_devs.c" ], "versions": [ { "version": "f23859748e3d530217b197e146a9ac84faf0a282", "lessThan": "fd7a97b2514cfc4b4cc067a27dd39bde2a8b1735", "status": "affected", "versionType": "git" }, { "version": "6f50b414f1a0d790f11a6438a3ad6d0577eb2c18", "lessThan": "73e35c1bdfa160b41fdbe204e02325f0687de506", "status": "affected", "versionType": "git" }, { "version": "36c75ce3bd299878fd9b238e9803d3817ddafbf3", "lessThan": "417918783bcfe0be135019df16a267b3af442efd", "status": "affected", "versionType": "git" }, { "version": "36c75ce3bd299878fd9b238e9803d3817ddafbf3", "lessThan": "5c53406098b599c420b031e6ec5ba8a2f3794c50", "status": "affected", "versionType": "git" }, { "version": "36c75ce3bd299878fd9b238e9803d3817ddafbf3", "lessThan": "4eafa810b042d985ec6bbf5b514414e73cee6f6f", "status": "affected", "versionType": "git" }, { "version": "36c75ce3bd299878fd9b238e9803d3817ddafbf3", "lessThan": "8d4b989d9c9afe5f185aa5853b666fc4617afe9e", "status": "affected", "versionType": "git" }, { "version": "2577fece583c7c05cda7ad50dde7638c962665e1", "status": "affected", "versionType": "git" }, { "version": "40ba3fa21250e361bdd8f00800b3e2cb6160de95", "status": "affected", "versionType": "git" }, { "version": "b0e7a935739f33ed2bd6868b89f97dd4c2683c26", "status": "affected", "versionType": "git" }, { "version": "66eb7b7f23dd9aec5356e7054dd3596ae7648ff5", "status": "affected", "versionType": "git" }, { "version": "b27751fb1f271bbb78d5993c0b10011628e40e18", "status": "affected", "versionType": "git" }, { "version": "6.1.63", "lessThan": "6.1.178", "status": "affected", "versionType": "semver" }, { "version": "6.6.2", "lessThan": "6.6.145", "status": "affected", "versionType": "semver" }, { "version": "4.19.299", "lessThan": "4.20", "status": "affected", "versionType": "semver" }, { "version": "5.4.261", "lessThan": "5.5", "status": "affected", "versionType": "semver" }, { "version": "5.10.201", "lessThan": "5.11", "status": "affected", "versionType": "semver" }, { "version": "5.15.139", "lessThan": "5.16", "status": "affected", "versionType": "semver" }, { "version": "6.5.12", "lessThan": "6.6", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "Documentation/driver-api/nvdimm/btt.rst", "drivers/nvdimm/nd.h", "drivers/nvdimm/region_devs.c" ], "versions": [ { "version": "6.7", "status": "affected" }, { "version": "0", "lessThan": "6.7", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.178", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.145", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.97", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.40", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.5", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "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": "6.1.63", "versionEndExcluding": "6.1.178" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.6.2", "versionEndExcluding": "6.6.145" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.12.97" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.18.40" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "7.1.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "7.2" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.19.299" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.4.261" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10.201" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15.139" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.5.12" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/fd7a97b2514cfc4b4cc067a27dd39bde2a8b1735" }, { "url": "https://git.kernel.org/stable/c/73e35c1bdfa160b41fdbe204e02325f0687de506" }, { "url": "https://git.kernel.org/stable/c/417918783bcfe0be135019df16a267b3af442efd" }, { "url": "https://git.kernel.org/stable/c/5c53406098b599c420b031e6ec5ba8a2f3794c50" }, { "url": "https://git.kernel.org/stable/c/4eafa810b042d985ec6bbf5b514414e73cee6f6f" }, { "url": "https://git.kernel.org/stable/c/8d4b989d9c9afe5f185aa5853b666fc4617afe9e" } ], "title": "nvdimm/btt: Handle preemption in BTT lane acquisition", "x_generator": { "engine": "bippy-1.2.0" } } } }