{"api_version":"1","generated_at":"2026-10-01T15:49:13+00:00","cve":"CVE-2026-90009","urls":{"html":"https://cve.report/CVE-2026-90009","api":"https://cve.report/api/cve/CVE-2026-90009.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-90009","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-90009"},"summary":{"title":"scsi: bsg: Fix TOCTOU in io_uring passthrough command setup","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: bsg: Fix TOCTOU in io_uring passthrough command setup\n\nscsi_bsg_uring_cmd() reads bsg_uring_cmd from the shared mmap'd SQE.\nUserspace can change a field after we check it and before we use it.\nrequest_len is the sharp case: it can grow past sizeof(scmd->cmnd) after\nthe bound check and overflow scmd->cmnd in copy_from_user().\n\nREAD_ONCE() the SQE fields we check or use into locals before use.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-16 11:17:13","updated_at":"2026-09-16 15:18:24"},"problem_types":[],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"7.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"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","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"7.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"baseScore":7.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/f033530105aa73d82c121d54b57f358e4865d2f4","name":"https://git.kernel.org/stable/c/f033530105aa73d82c121d54b57f358e4865d2f4","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/4b3c5965fca99f62d31c963294bd5b23cc488e97","name":"https://git.kernel.org/stable/c/4b3c5965fca99f62d31c963294bd5b23cc488e97","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-90009","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-90009","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7b6d3255e7f8c6df2d21504c47808e3ce84649ac f033530105aa73d82c121d54b57f358e4865d2f4 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7b6d3255e7f8c6df2d21504c47808e3ce84649ac 4b3c5965fca99f62d31c963294bd5b23cc488e97 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7.1","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.5 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc2 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["drivers/scsi/scsi_bsg.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"f033530105aa73d82c121d54b57f358e4865d2f4","status":"affected","version":"7b6d3255e7f8c6df2d21504c47808e3ce84649ac","versionType":"git"},{"lessThan":"4b3c5965fca99f62d31c963294bd5b23cc488e97","status":"affected","version":"7b6d3255e7f8c6df2d21504c47808e3ce84649ac","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["drivers/scsi/scsi_bsg.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"7.1"},{"lessThan":"7.1","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.5","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc2","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.5","versionStartIncluding":"7.1","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc2","versionStartIncluding":"7.1","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: bsg: Fix TOCTOU in io_uring passthrough command setup\n\nscsi_bsg_uring_cmd() reads bsg_uring_cmd from the shared mmap'd SQE.\nUserspace can change a field after we check it and before we use it.\nrequest_len is the sharp case: it can grow past sizeof(scmd->cmnd) after\nthe bound check and overflow scmd->cmnd in copy_from_user().\n\nREAD_ONCE() the SQE fields we check or use into locals before use."}],"metrics":[{"cvssV3_1":{"baseScore":7.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"scenarios":[{"lang":"en","value":"AV:L - scsi_bsg_uring_cmd() is reached only via a local io_uring IORING_OP_URING_CMD on a SCSI BSG device node (/dev/bsg/<h:c:i:l>); io_uring and BSG are local syscall/device paths, not a network protocol handler.\nAC:L - The attacker owns both sides of the TOCTOU: one thread submits the uring_cmd while another rewrites request_len in the shared mmap'd SQE. The inline issue path never copies the SQE first, and scsi_alloc_request() sits between the bound check and copy_from_user, making the race attacker-driven and retryable.\nPR:L - bsg_open() has no capability check; access is only DAC on /dev/bsg/* for ordinary SCSI devices. scsi_cmd_allowed() runs after the overflow. Disk/cdrom group membership and uaccess on removable SCSI/USB devices grant this to unprivileged local users without init-namespace root.\nUI:N - The attacker opens the BSG node, creates an io_uring ring with SQE128/CQE32, and submits the racing passthrough command themselves; no victim action is required.\nS:U - The overflow corrupts the blk-mq scsi_cmnd PDU and adjacent kernel heap in the same host kernel security authority, enabling local privilege escalation rather than a VM, IOMMU, or sandbox boundary crossing.\nC:H - copy_from_user() overflows the 32-byte scmd->cmnd into scsi_cmnd pointer fields (sdb, sense_buffer, host_scribble) and adjacent heap with attacker-controlled bytes, which can be groomed into kernel memory disclosure.\nI:H - The same attacker-controlled heap overflow overwrites kernel pointers and adjacent blk-mq request objects, providing a write primitive exploitable for control-flow hijacking and privilege escalation.\nA:H - A large request_len smash or later use of corrupted scsi_cmnd pointers causes a kernel oops or panic; even a failed copy_from_user still writes through kernel memory until a fault, then frees the corrupted request."}]}],"providerMetadata":{"dateUpdated":"2026-09-16T14:41:25.065Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/f033530105aa73d82c121d54b57f358e4865d2f4"},{"url":"https://git.kernel.org/stable/c/4b3c5965fca99f62d31c963294bd5b23cc488e97"}],"title":"scsi: bsg: Fix TOCTOU in io_uring passthrough command setup","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-90009","datePublished":"2026-09-16T10:33:17.446Z","dateReserved":"2026-09-11T19:38:34.781Z","dateUpdated":"2026-09-16T14:41:25.065Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-16 11:17:13","lastModifiedDate":"2026-09-16 15:18:24","problem_types":[],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"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","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":5.9}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"90009","Ordinal":"1","Title":"scsi: bsg: Fix TOCTOU in io_uring passthrough command setup","CVE":"CVE-2026-90009","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"90009","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: bsg: Fix TOCTOU in io_uring passthrough command setup\n\nscsi_bsg_uring_cmd() reads bsg_uring_cmd from the shared mmap'd SQE.\nUserspace can change a field after we check it and before we use it.\nrequest_len is the sharp case: it can grow past sizeof(scmd->cmnd) after\nthe bound check and overflow scmd->cmnd in copy_from_user().\n\nREAD_ONCE() the SQE fields we check or use into locals before use.","Type":"Description","Title":"scsi: bsg: Fix TOCTOU in io_uring passthrough command setup"}]}}}