CVE-2026-89584

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-89584", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.729Z", "datePublished": "2026-09-11T19:44:49.838Z", "dateUpdated": "2026-10-19T08:49:17.054Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:49:17.054Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nblock: validate user space vectors during extraction\n\nThe bio-based drivers don't necessarily check the alignment split, and\nstacking block drivers don't always handle a misalignment detected after\nsubmitting the bio. Validate user vectors against the device's\ndma_alignment as the bio is built from the iov_iter, rejecting\nmisaligned early with -EINVAL."}], "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 - Missing dma_alignment validation is in bio_iov_iter_get_pages()/iov_iter_extract_bvecs(), reached only via local O_DIRECT (preadv/pwritev/io_uring) through blkdev_direct_IO() and iomap_dio_bio_iter_one() on ext4/XFS/btrfs/f2fs or raw block devices; ksmbd/nfsd do not feed attacker-controlled user iovecs into this path.\nAC:L - After the simplified DIO checks, only file offset and total length must be logical-block aligned; the attacker fully controls each iovec address and length and can submit misaligned buffers or io_uring registered buffers deterministically, with no race or attacker-uncontrolled layout required.\nPR:L - Any unprivileged user with read or write access to a regular file on an iomap DIO filesystem, or to a block device they can open, can issue O_DIRECT with no capability; stacked dm/md/LUKS setups are a deployment precondition, not a privilege the attacker must obtain.\nUI:N - The attacker opens their own file or device and issues the misaligned O_DIRECT I/O themselves; no separate victim must mount media, confirm a prompt, or otherwise participate.\nS:U - Impact stays inside the host kernel block layer and stacked devices (invalid DMA, driver mishandling, array denial of service) and does not cross a VM, hypervisor, IOMMU, or sandbox boundary.\nC:H - Bio-based drivers (dm, md) skip __bio_split_to_limits() on normal I/O, so attacker-controlled bvec offsets reach DMA and crypto SG lists such as dm-crypt sg_set_page(). Unaligned or page-crossing DMA, including non-coherent cache-line effects and hardware address rounding, can read adjacent memory.\nI:H - The same unvalidated user vectors are programmed into device DMA and driver scatterlists; misaligned writes, hardware address masking, and cache-line tearing on non-coherent DMA can corrupt adjacent memory or neighboring disk blocks, and drivers that assume aligned bvecs can perform out-of-bounds writes.\nA:H - Misaligned bios are known to degrade md/raid1 and dm-mirror arrays when lower devices return BLK_STS_INVAL, hang dm-io on byte-granular fragments, and can oops or hang bio-based drivers and DMA engines that reject unaligned segments, all kernel-level availability failures."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["block/bio.c", "block/blk-map.c", "block/fops.c", "fs/iomap/direct-io.c", "include/linux/bio.h", "include/linux/uio.h", "lib/iov_iter.c"], "versions": [{"version": "5ff3f74e145adc79b49668adb8de276446acf6be", "lessThan": "d44a97a3b1c00cc571245124e23e5ceb0a0225a0", "status": "affected", "versionType": "git"}, {"version": "5ff3f74e145adc79b49668adb8de276446acf6be", "lessThan": "14b007e178811db72fbb1ebb3535160db6ec1e6a", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["block/bio.c", "block/blk-map.c", "block/fops.c", "fs/iomap/direct-io.c", "include/linux/bio.h", "include/linux/uio.h", "lib/iov_iter.c"], "versions": [{"version": "6.18", "status": "affected"}, {"version": "0", "lessThan": "6.18", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.4", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3", "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": "6.18", "versionEndExcluding": "7.2.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/d44a97a3b1c00cc571245124e23e5ceb0a0225a0"}, {"url": "https://git.kernel.org/stable/c/14b007e178811db72fbb1ebb3535160db6ec1e6a"}], "title": "block: validate user space vectors during extraction", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["block/bio.c", "block/blk-map.c", "block/fops.c", "fs/iomap/direct-io.c", "include/linux/bio.h", "include/linux/uio.h", "lib/iov_iter.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "d44a97a3b1c00cc571245124e23e5ceb0a0225a0", "status": "affected", "version": "5ff3f74e145adc79b49668adb8de276446acf6be", "versionType": "git"}, {"lessThan": "14b007e178811db72fbb1ebb3535160db6ec1e6a", "status": "affected", "version": "5ff3f74e145adc79b49668adb8de276446acf6be", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["block/bio.c", "block/blk-map.c", "block/fops.c", "fs/iomap/direct-io.c", "include/linux/bio.h", "include/linux/uio.h", "lib/iov_iter.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.18"}, {"lessThan": "6.18", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.4", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nblock: validate user space vectors during extraction\n\nThe bio-based drivers don't necessarily check the alignment split, and\nstacking block drivers don't always handle a misalignment detected after\nsubmitting the bio. Validate user vectors against the device's\ndma_alignment as the bio is built from the iov_iter, rejecting\nmisaligned early with -EINVAL."}], "id": "CVE-2026-89584", "lastModified": "2026-10-19T09:17:54.550", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-09-11T20:19:42.797", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/14b007e178811db72fbb1ebb3535160db6ec1e6a"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/d44a97a3b1c00cc571245124e23e5ceb0a0225a0"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: Linux Kernel: Denial of Service due to improper user space vector validation in block layer", "id": "2532265", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2532265"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.7", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-1288", "details": ["A flaw was found in the Linux kernel's block layer. This vulnerability arises from insufficient validation of user-space data structures (vectors) against the device's Direct Memory Access (DMA) alignment requirements. A local attacker could exploit this by providing misaligned data, causing the system to reject the input with an error and potentially leading to a Denial of Service (DoS)."], "name": "CVE-2026-89584", "public_date": "2026-09-11T19:44:49Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-89584\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-89584\nhttps://git.kernel.org/stable/c/14b007e178811db72fbb1ebb3535160db6ec1e6a\nhttps://git.kernel.org/stable/c/d44a97a3b1c00cc571245124e23e5ceb0a0225a0"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5ff3f74e145adc79b49668adb8de276446acf6be,d44a97a3b1c00cc571245124e23e5ceb0a0225a0)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5ff3f74e145adc79b49668adb8de276446acf6be,14b007e178811db72fbb1ebb3535160db6ec1e6a)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "6.18"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,6.18)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.4,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.3-rc1,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-09-12T06:45:10.803560+00:00", "updated": "2026-09-15T21:45:17.660337+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}