CVE-2025-40216

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2025-40216", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T07:20:57.179Z", "datePublished": "2025-12-04T14:14:14.690Z", "dateUpdated": "2026-10-15T22:02:41.119Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:08:41.986Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/rsrc: don't rely on user vaddr alignment\n\nThere is no guaranteed alignment for user pointers, however the\ncalculation of an offset of the first page into a folio after coalescing\nuses some weird bit mask logic, get rid of it."}], "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 vulnerable code is reached only through io_uring syscalls (io_uring_setup/io_uring_register with IORING_REGISTER_BUFFERS), which require local access; there is no network reachability.\nAC:L - The attacker fully controls the trigger \u2014 allocating a multi-page folio (mTHP/hugetlb) and creating a VA-vs-folio misalignment, then registering it \u2014 with no race or externally-determined condition, making it deterministically reproducible.\nPR:L - IORING_REGISTER_BUFFERS has no capability check and io_uring is available to unprivileged users by default; a basic local user can register a coalescable large-folio buffer.\nUI:N - The entire flow (map memory, register buffer, submit fixed I/O) is performed by the attacker's own process with no victim interaction.\nS:U - The corruption stays within the kernel's own security scope; there is no VM/IOMMU/sandbox boundary being crossed.\nC:H - The wrong bv_offset plus mis-driven seg_skip/nr_segs arithmetic can read out of the bvec array and at unintended folio offsets (including shared file-backed folios), disclosing kernel heap and cross-mapping memory.\nI:H - WRITE_FIXED with the miscomputed offset writes attacker-supplied I/O data at wrong offsets and potential wild page pointers, giving an out-of-bounds write / memory-corruption primitive.\nA:H - Dereferencing a garbage bio_vec / wild bv_page during fixed-buffer I/O readily oopses or panics the kernel."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["io_uring/rsrc.c", "io_uring/rsrc.h"], "versions": [{"version": "a8edbb424b1391b077407c75d8f5d2ede77aa70d", "lessThan": "50998b0ae7d9d552e96d8b7239981cf05f65eff5", "status": "affected", "versionType": "git"}, {"version": "a8edbb424b1391b077407c75d8f5d2ede77aa70d", "lessThan": "f16769241594be59387b56ab525e327f54377e60", "status": "affected", "versionType": "git"}, {"version": "a8edbb424b1391b077407c75d8f5d2ede77aa70d", "lessThan": "3a3c6d61577dbb23c09df3e21f6f9eda1ecd634b", "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/rsrc.c", "io_uring/rsrc.h"], "versions": [{"version": "6.12", "status": "affected"}, {"version": "0", "lessThan": "6.12", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.36", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.15.5", "lessThanOrEqual": "6.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.16", "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": "6.12", "versionEndExcluding": "6.12.36"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12", "versionEndExcluding": "6.15.5"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.12", "versionEndExcluding": "6.16"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/50998b0ae7d9d552e96d8b7239981cf05f65eff5"}, {"url": "https://git.kernel.org/stable/c/f16769241594be59387b56ab525e327f54377e60"}, {"url": "https://git.kernel.org/stable/c/3a3c6d61577dbb23c09df3e21f6f9eda1ecd634b"}], "title": "io_uring/rsrc: don't rely on user vaddr alignment", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2025-40216", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-15T21:58:17.038442Z"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-15T22:02:41.119Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2025-40216", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "version": "2.0.3", "timestamp": "2026-10-15T21:58:17.038442Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-15T21:58:17.988Z"}}], "cna": {"title": "io_uring/rsrc: don't rely on user vaddr alignment", "metrics": [{"cvssV3_1": {"version": "3.1", "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"}, "scenarios": [{"lang": "en", "value": "AV:L - The vulnerable code is reached only through io_uring syscalls (io_uring_setup/io_uring_register with IORING_REGISTER_BUFFERS), which require local access; there is no network reachability.\nAC:L - The attacker fully controls the trigger \u2014 allocating a multi-page folio (mTHP/hugetlb) and creating a VA-vs-folio misalignment, then registering it \u2014 with no race or externally-determined condition, making it deterministically reproducible.\nPR:L - IORING_REGISTER_BUFFERS has no capability check and io_uring is available to unprivileged users by default; a basic local user can register a coalescable large-folio buffer.\nUI:N - The entire flow (map memory, register buffer, submit fixed I/O) is performed by the attacker's own process with no victim interaction.\nS:U - The corruption stays within the kernel's own security scope; there is no VM/IOMMU/sandbox boundary being crossed.\nC:H - The wrong bv_offset plus mis-driven seg_skip/nr_segs arithmetic can read out of the bvec array and at unintended folio offsets (including shared file-backed folios), disclosing kernel heap and cross-mapping memory.\nI:H - WRITE_FIXED with the miscomputed offset writes attacker-supplied I/O data at wrong offsets and potential wild page pointers, giving an out-of-bounds write / memory-corruption primitive.\nA:H - Dereferencing a garbage bio_vec / wild bv_page during fixed-buffer I/O readily oopses or panics the kernel."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "a8edbb424b1391b077407c75d8f5d2ede77aa70d", "lessThan": "50998b0ae7d9d552e96d8b7239981cf05f65eff5", "versionType": "git"}, {"status": "affected", "version": "a8edbb424b1391b077407c75d8f5d2ede77aa70d", "lessThan": "f16769241594be59387b56ab525e327f54377e60", "versionType": "git"}, {"status": "affected", "version": "a8edbb424b1391b077407c75d8f5d2ede77aa70d", "lessThan": "3a3c6d61577dbb23c09df3e21f6f9eda1ecd634b", "versionType": "git"}], "programFiles": ["io_uring/rsrc.c", "io_uring/rsrc.h"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "6.12"}, {"status": "unaffected", "version": "0", "lessThan": "6.12", "versionType": "semver"}, {"status": "unaffected", "version": "6.12.36", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.15.5", "versionType": "semver", "lessThanOrEqual": "6.15.*"}, {"status": "unaffected", "version": "6.16", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["io_uring/rsrc.c", "io_uring/rsrc.h"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/50998b0ae7d9d552e96d8b7239981cf05f65eff5"}, {"url": "https://git.kernel.org/stable/c/f16769241594be59387b56ab525e327f54377e60"}, {"url": "https://git.kernel.org/stable/c/3a3c6d61577dbb23c09df3e21f6f9eda1ecd634b"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring/rsrc: don't rely on user vaddr alignment\n\nThere is no guaranteed alignment for user pointers, however the\ncalculation of an offset of the first page into a folio after coalescing\nuses some weird bit mask logic, get rid of it."}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.12.36", "versionStartIncluding": "6.12"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.15.5", "versionStartIncluding": "6.12"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.16", "versionStartIncluding": "6.12"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:08:41.986Z"}}}, "cveMetadata": {"cveId": "CVE-2025-40216", "state": "PUBLISHED", "dateUpdated": "2026-10-15T22:02:41.119Z", "dateReserved": "2025-04-16T07:20:57.179Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2025-12-04T14:14:14.690Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["io_uring/rsrc.c", "io_uring/rsrc.h"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "50998b0ae7d9d552e96d8b7239981cf05f65eff5", "status": "affected", "version": "a8edbb424b1391b077407c75d8f5d2ede77aa70d", "versionType": "git"}, {"lessThan": "f16769241594be59387b56ab525e327f54377e60", "status": "affected", "version": "a8edbb424b1391b077407c75d8f5d2ede77aa70d", "versionType": "git"}, {"lessThan": "3a3c6d61577dbb23c09df3e21f6f9eda1ecd634b", "status": "affected", "version": "a8edbb424b1391b077407c75d8f5d2ede77aa70d", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["io_uring/rsrc.c", "io_uring/rsrc.h"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.12"}, {"lessThan": "6.12", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.36", "versionType": "semver"}, {"lessThanOrEqual": "6.15.*", "status": "unaffected", "version": "6.15.5", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "6.16", "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\nio_uring/rsrc: don't rely on user vaddr alignment\n\nThere is no guaranteed alignment for user pointers, however the\ncalculation of an offset of the first page into a folio after coalescing\nuses some weird bit mask logic, get rid of it."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nio_uring/rsrc: no depender de la alineaci\u00f3n de vaddr de usuario\n\nNo hay una alineaci\u00f3n garantizada para los punteros de usuario; sin embargo, el c\u00e1lculo de un desplazamiento de la primera p\u00e1gina en un folio despu\u00e9s de la coalescencia utiliza una l\u00f3gica de m\u00e1scara de bits extra\u00f1a, deshacerse de ella."}], "id": "CVE-2025-40216", "lastModified": "2026-10-19T21:10:00.160", "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"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2025-40216", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-10-15T21:58:17.038442Z", "version": "2.0.3"}}]}, "published": "2025-12-04T15:15:57.300", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/3a3c6d61577dbb23c09df3e21f6f9eda1ecd634b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/50998b0ae7d9d552e96d8b7239981cf05f65eff5"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f16769241594be59387b56ab525e327f54377e60"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Deferred"}

{"bugzilla": {"description": "kernel: io_uring/rsrc: don't rely on user vaddr alignment", "id": "2418801", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2418801"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.0", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "details": ["In the Linux kernel, the following vulnerability has been resolved:\nio_uring/rsrc: don't rely on user vaddr alignment\nThere is no guaranteed alignment for user pointers, however the\ncalculation of an offset of the first page into a folio after coalescing\nuses some weird bit mask logic, get rid of it."], "name": "CVE-2025-40216", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2025-12-04T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2025-40216\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-40216\nhttps://lore.kernel.org/linux-cve-announce/2025120417-CVE-2025-40216-d79f@gregkh/T"], "threat_severity": "Moderate"}

{}