{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-43442", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-05-01T14:12:56.009Z", "datePublished": "2026-05-08T14:22:10.656Z", "dateUpdated": "2026-08-05T12:27:59.003Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:27:59.003Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring: fix physical SQE bounds check for SQE_MIXED 128-byte ops\n\nWhen IORING_SETUP_SQE_MIXED is used without IORING_SETUP_NO_SQARRAY,\nthe boundary check for 128-byte SQE operations in io_init_req()\nvalidated the logical SQ head position rather than the physical SQE\nindex.\n\nThe existing check:\n\n !(ctx->cached_sq_head & (ctx->sq_entries - 1))\n\nensures the logical position isn't at the end of the ring, which is\ncorrect for NO_SQARRAY rings where physical == logical. However, when\nsq_array is present, an unprivileged user can remap any logical\nposition to an arbitrary physical index via sq_array. Setting\nsq_array[N] = sq_entries - 1 places a 128-byte operation at the last\nphysical SQE slot, causing the 128-byte memcpy in\nio_uring_cmd_sqe_copy() to read 64 bytes past the end of the SQE\narray.\n\nReplace the cached_sq_head alignment check with a direct validation\nof the physical SQE index, which correctly handles both sq_array and\nNO_SQARRAY cases." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H", "baseScore": 7.1, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The vulnerable path is reached through local io_uring syscalls and userspace-controlled SQ/SQE mappings, not by remote packets or physical access.\nAC:L - The attacker controls ring setup flags, sq_array contents, SQEs, and submission order; no race or external timing condition is required.\nPR:L - A basic unprivileged local user can create io_uring instances on the default kernel.io_uring_disabled=0 configuration and can use accessible uring_cmd files such as /dev/null or sockets.\nUI:N - Exploitation only requires the attacker's own syscall sequence and mapped ring manipulation, with no victim action.\nS:U - The issue remains within the kernel security authority and does not cross a VM, IOMMU, or other separate security boundary.\nC:H - The bad 128-byte memcpy can read 64 bytes past the SQE array; for page-boundary layouts this can read adjacent kernel memory, so confidentiality impact is high.\nI:N - The investigated primitive is an out-of-bounds read into a valid request buffer, with no out-of-bounds write or direct arbitrary modification primitive identified.\nA:H - The same out-of-bounds read can fault or trigger kernel diagnostics/oops conditions and is repeatable by the local attacker." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "io_uring/io_uring.c" ], "versions": [ { "version": "1cba30bf9fdd6c982708f3587f609a30c370d889", "lessThan": "1f794f9bed3e5cf7250a3b4daf112a72ed1513e9", "status": "affected", "versionType": "git" }, { "version": "1cba30bf9fdd6c982708f3587f609a30c370d889", "lessThan": "6f02c6b196036dbb6defb4647d8707d29b7fe95b", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "io_uring/io_uring.c" ], "versions": [ { "version": "6.19", "status": "affected" }, { "version": "0", "lessThan": "6.19", "status": "unaffected", "versionType": "semver" }, { "version": "6.19.9", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0", "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": "6.19", "versionEndExcluding": "6.19.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "7.0" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/1f794f9bed3e5cf7250a3b4daf112a72ed1513e9" }, { "url": "https://git.kernel.org/stable/c/6f02c6b196036dbb6defb4647d8707d29b7fe95b" } ], "title": "io_uring: fix physical SQE bounds check for SQE_MIXED 128-byte ops", "x_generator": { "engine": "bippy-1.2.0" } } } }