CVE-2026-45942

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But got 8192 blocks\n\nAnalysis and experimentation confirmed that the issue is caused by a\nrace condition between page migration and bitmap modification. Although\nthis timing window is extremely narrow, it is still hit in practice:\n\nfolio_lock ext4_mb_load_buddy\n__migrate_folio\n check ref count\n folio_mc_copy __filemap_get_folio\n folio_try_get(folio)\n ......\n mb_mark_used\n ext4_mb_unload_buddy\n __folio_migrate_mapping\n folio_ref_freeze\nfolio_unlock\n\nThe root cause of this issue is that the fast path of load_buddy only\nincrements the folio's reference count, which is insufficient to prevent\nconcurrent folio migration. We observed that the folio migration process\nacquires the folio lock. Therefore, we can determine whether to take the\nfast path in load_buddy by checking the lock status. If the folio is\nlocked, we opt for the slow path (which acquires the lock) to close this\nconcurrency window.\n\nAdditionally, this change addresses the following issues:\n\nWhen the DOUBLE_CHECK macro is enabled to inspect bitmap-related\nissues, the following error may be triggered:\n\ncorruption in group 324 at byte 784(6272): f in copy != ff on\ndisk/prealloc\n\nAnalysis reveals that this is a false positive. There is a specific race\nwindow where the bitmap and the group descriptor become momentarily\ninconsistent, leading to this error report:\n\next4_mb_load_buddy ext4_mb_load_buddy\n __filemap_get_folio(create|lock)\n folio_lock\n ext4_mb_init_cache\n folio_mark_uptodate\n __filemap_get_folio(no lock)\n ......\n mb_mark_used\n mb_mark_used_double\n mb_cmp_bitmaps\n mb_set_bits(e4b->bd_bitmap)\n folio_unlock\n\nThe original logic assumed that since mb_cmp_bitmaps is called when the\nbitmap is newly loaded from disk, the folio lock would be sufficient to\nprevent concurrent access. However, this overlooks a specific race\ncondition: if another process attempts to load buddy and finds the folio\nis already in an uptodate state, it will immediately begin using it without\nholding folio lock."}], "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 vulnerability is reached through local filesystem block-allocation activity combined with local folio migration (compaction/NUMA/huge-page reclaim), which is a kernel memory-management event an attacker induces locally; there is no remote path that controls the migration side of the race.\nAC:L - The attacker controls both sides of the race\u2014heavy block-allocation I/O plus memory pressure that forces folio migration\u2014and the commit confirms the window \"is still hit in practice\" under sustained workloads, so it is reliably reproducible by an attacker-constructed workload.\nPR:L - An ordinary unprivileged local user with write access to any ext4 filesystem (e.g., /tmp or /home) can drive block allocation and induce memory migration; no elevated capabilities are required.\nUI:N - The attacker performs all actions (file writes plus memory pressure) on an already-mounted filesystem with no action by any other user.\nS:U - The corruption is confined to the ext4 filesystem and kernel within the same security authority; no VM, sandbox, or IOMMU boundary is crossed.\nC:H - A lost bitmap update can cause block double-allocation, assigning the same physical block to two inodes so one user can read data written by another on a shared filesystem, constituting significant information disclosure.\nI:H - The race corrupts buddy-bitmap/group-descriptor consistency and can double-allocate blocks, leading to file-data corruption (one file's writes overwriting another's) and persistent on-disk metadata inconsistency.\nA:H - Detected inconsistency invokes ext4_grp_locked_error()/ext4_handle_error(), which aborts the journal and remounts the filesystem read-only (or panics the kernel with errors=panic), rendering the filesystem\u2014potentially the root filesystem\u2014unavailable."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/ext4/mballoc.c"], "versions": [{"version": "c9de560ded61faa5b754137b7753da252391c55a", "lessThan": "a3a7d360252c0d84ae8bda067fb296c9e82928d3", "status": "affected", "versionType": "git"}, {"version": "c9de560ded61faa5b754137b7753da252391c55a", "lessThan": "57e83bfbe1e412ac42daced2086f3c6f9a17bba0", "status": "affected", "versionType": "git"}, {"version": "c9de560ded61faa5b754137b7753da252391c55a", "lessThan": "c05033cfc5c7699cd4df8d48cef94d01da755f24", "status": "affected", "versionType": "git"}, {"version": "c9de560ded61faa5b754137b7753da252391c55a", "lessThan": 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"unaffected", "versionType": "semver"}, {"version": "6.18.14", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.19.4", "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": "2.6.25", "versionEndExcluding": "6.1.191"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "6.6.130"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.25", "versionEndExcluding": "6.12.75"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": 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there is no remote path that controls the migration side of the race.\nAC:L - The attacker controls both sides of the race\u2014heavy block-allocation I/O plus memory pressure that forces folio migration\u2014and the commit confirms the window \"is still hit in practice\" under sustained workloads, so it is reliably reproducible by an attacker-constructed workload.\nPR:L - An ordinary unprivileged local user with write access to any ext4 filesystem (e.g., /tmp or /home) can drive block allocation and induce memory migration; no elevated capabilities are required.\nUI:N - The attacker performs all actions (file writes plus memory pressure) on an already-mounted filesystem with no action by any other user.\nS:U - The corruption is confined to the ext4 filesystem and kernel within the same security authority; no VM, sandbox, or IOMMU boundary is crossed.\nC:H - A lost bitmap update can cause block double-allocation, assigning the same physical block to two inodes so one user can read data written by another on a shared filesystem, constituting significant information disclosure.\nI:H - The race corrupts buddy-bitmap/group-descriptor consistency and can double-allocate blocks, leading to file-data corruption (one file's writes overwriting another's) and persistent on-disk metadata inconsistency.\nA:H - Detected inconsistency invokes ext4_grp_locked_error()/ext4_handle_error(), which aborts the journal and remounts the filesystem read-only (or panics the kernel with errors=panic), rendering the filesystem\u2014potentially the root filesystem\u2014unavailable."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "c9de560ded61faa5b754137b7753da252391c55a", "lessThan": "a3a7d360252c0d84ae8bda067fb296c9e82928d3", "versionType": "git"}, {"status": "affected", "version": "c9de560ded61faa5b754137b7753da252391c55a", "lessThan": "57e83bfbe1e412ac42daced2086f3c6f9a17bba0", "versionType": "git"}, {"status": "affected", "version": "c9de560ded61faa5b754137b7753da252391c55a", "lessThan": "c05033cfc5c7699cd4df8d48cef94d01da755f24", "versionType": "git"}, {"status": "affected", "version": "c9de560ded61faa5b754137b7753da252391c55a", "lessThan": "29a07d691d282faf38c33d4b61839b89399110f9", "versionType": "git"}, {"status": "affected", "version": "c9de560ded61faa5b754137b7753da252391c55a", "lessThan": "f29709a7a3fc38f5015d850504762cdef0e151f9", "versionType": "git"}, {"status": "affected", "version": "c9de560ded61faa5b754137b7753da252391c55a", "lessThan": "bdc56a9c46b2a99c12313122b9352b619a2e719e", "versionType": "git"}], "programFiles": ["fs/ext4/mballoc.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "2.6.25"}, {"status": "unaffected", "version": "0", "lessThan": "2.6.25", "versionType": "semver"}, {"status": "unaffected", "version": "6.1.191", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.130", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.75", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.14", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "6.19.4", "versionType": "semver", "lessThanOrEqual": "6.19.*"}, {"status": "unaffected", "version": "7.0", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["fs/ext4/mballoc.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/a3a7d360252c0d84ae8bda067fb296c9e82928d3"}, {"url": "https://git.kernel.org/stable/c/57e83bfbe1e412ac42daced2086f3c6f9a17bba0"}, {"url": "https://git.kernel.org/stable/c/c05033cfc5c7699cd4df8d48cef94d01da755f24"}, {"url": "https://git.kernel.org/stable/c/29a07d691d282faf38c33d4b61839b89399110f9"}, {"url": "https://git.kernel.org/stable/c/f29709a7a3fc38f5015d850504762cdef0e151f9"}, {"url": "https://git.kernel.org/stable/c/bdc56a9c46b2a99c12313122b9352b619a2e719e"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix e4b bitmap inconsistency reports\n\nA bitmap inconsistency issue was observed during stress tests under\nmixed huge-page workloads. Ext4 reported multiple e4b bitmap check\nfailures like:\n\next4_mb_complex_scan_group:2508: group 350, 8179 free clusters as\nper group info. But got 8192 blocks\n\nAnalysis and experimentation confirmed that the issue is caused by a\nrace condition between page migration and bitmap modification. Although\nthis timing window is extremely narrow, it is still hit in practice:\n\nfolio_lock ext4_mb_load_buddy\n__migrate_folio\n check ref count\n folio_mc_copy __filemap_get_folio\n folio_try_get(folio)\n ......\n mb_mark_used\n ext4_mb_unload_buddy\n __folio_migrate_mapping\n folio_ref_freeze\nfolio_unlock\n\nThe root cause of this issue is that the fast path of load_buddy only\nincrements the folio's reference count, which is insufficient to prevent\nconcurrent folio migration. We observed that the folio migration process\nacquires the folio lock. Therefore, we can determine whether to take the\nfast path in load_buddy by checking the lock status. If the folio is\nlocked, we opt for the slow path (which acquires the lock) to close this\nconcurrency window.\n\nAdditionally, this change addresses the following issues:\n\nWhen the DOUBLE_CHECK macro is enabled to inspect bitmap-related\nissues, the following error may be triggered:\n\ncorruption in group 324 at byte 784(6272): f in copy != ff on\ndisk/prealloc\n\nAnalysis reveals that this is a false positive. There is a specific race\nwindow where the bitmap and the group descriptor become momentarily\ninconsistent, leading to this error report:\n\next4_mb_load_buddy ext4_mb_load_buddy\n __filemap_get_folio(create|lock)\n folio_lock\n ext4_mb_init_cache\n folio_mark_uptodate\n __filemap_get_folio(no lock)\n ......\n mb_mark_used\n mb_mark_used_double\n mb_cmp_bitmaps\n mb_set_bits(e4b->bd_bitmap)\n folio_unlock\n\nThe original logic assumed that since mb_cmp_bitmaps is called when the\nbitmap is newly loaded from disk, the folio lock would be sufficient to\nprevent concurrent access. However, this overlooks a specific race\ncondition: if another process attempts to load buddy and finds the folio\nis already in an uptodate state, it will immediately begin using it without\nholding folio lock."}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.1.191", "versionStartIncluding": "2.6.25"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.6.130", "versionStartIncluding": "2.6.25"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.12.75", "versionStartIncluding": "2.6.25"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.18.14", "versionStartIncluding": "2.6.25"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.19.4", "versionStartIncluding": "2.6.25"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "7.0", "versionStartIncluding": "2.6.25"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-30T12:25:46.692Z"}}}, "cveMetadata": {"cveId": "CVE-2026-45942", "state": "PUBLISHED", "dateUpdated": "2026-10-30T12:25:46.692Z", "dateReserved": "2026-05-13T15:03:33.087Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2026-05-27T12:17:57.950Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/ext4/mballoc.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "a3a7d360252c0d84ae8bda067fb296c9e82928d3", "status": "affected", "version": "c9de560ded61faa5b754137b7753da252391c55a", "versionType": "git"}, {"lessThan": "57e83bfbe1e412ac42daced2086f3c6f9a17bba0", "status": "affected", "version": "c9de560ded61faa5b754137b7753da252391c55a", "versionType": "git"}, {"lessThan": "c05033cfc5c7699cd4df8d48cef94d01da755f24", "status": "affected", "version": "c9de560ded61faa5b754137b7753da252391c55a", "versionType": "git"}, {"lessThan": "29a07d691d282faf38c33d4b61839b89399110f9", "status": "affected", "version": "c9de560ded61faa5b754137b7753da252391c55a", "versionType": "git"}, {"lessThan": "f29709a7a3fc38f5015d850504762cdef0e151f9", "status": "affected", "version": "c9de560ded61faa5b754137b7753da252391c55a", "versionType": "git"}, {"lessThan": "bdc56a9c46b2a99c12313122b9352b619a2e719e", "status": "affected", "version": "c9de560ded61faa5b754137b7753da252391c55a", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/ext4/mballoc.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "2.6.25"}, {"lessThan": "2.6.25", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.191", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.130", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.75", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.14", "versionType": "semver"}, {"lessThanOrEqual": "6.19.*", "status": "unaffected", "version": "6.19.4", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.0", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "F63C0224-D6A0-4E52-A75A-D9016CE6983E", "versionEndExcluding": "6.6.130", "versionStartIncluding": "2.6.25", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "BCE16369-98ED-41CF-8995-DFDC10B288D2", "versionEndExcluding": "6.12.75", "versionStartIncluding": "6.7", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "BF463CB7-1F58-4607-B847-77ED23E4B9B7", "versionEndExcluding": "6.18.14", "versionStartIncluding": "6.13", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "672A3E79-EC03-479D-8503-361DFBDC8092", "versionEndExcluding": "6.19.4", "versionStartIncluding": "6.19", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix e4b bitmap inconsistency reports\n\nA bitmap inconsistency issue was observed during stress tests under\nmixed huge-page workloads. Ext4 reported multiple e4b bitmap check\nfailures like:\n\next4_mb_complex_scan_group:2508: group 350, 8179 free clusters as\nper group info. But got 8192 blocks\n\nAnalysis and experimentation confirmed that the issue is caused by a\nrace condition between page migration and bitmap modification. Although\nthis timing window is extremely narrow, it is still hit in practice:\n\nfolio_lock ext4_mb_load_buddy\n__migrate_folio\n check ref count\n folio_mc_copy __filemap_get_folio\n folio_try_get(folio)\n ......\n mb_mark_used\n ext4_mb_unload_buddy\n __folio_migrate_mapping\n folio_ref_freeze\nfolio_unlock\n\nThe root cause of this issue is that the fast path of load_buddy only\nincrements the folio's reference count, which is insufficient to prevent\nconcurrent folio migration. We observed that the folio migration process\nacquires the folio lock. Therefore, we can determine whether to take the\nfast path in load_buddy by checking the lock status. If the folio is\nlocked, we opt for the slow path (which acquires the lock) to close this\nconcurrency window.\n\nAdditionally, this change addresses the following issues:\n\nWhen the DOUBLE_CHECK macro is enabled to inspect bitmap-related\nissues, the following error may be triggered:\n\ncorruption in group 324 at byte 784(6272): f in copy != ff on\ndisk/prealloc\n\nAnalysis reveals that this is a false positive. There is a specific race\nwindow where the bitmap and the group descriptor become momentarily\ninconsistent, leading to this error report:\n\next4_mb_load_buddy ext4_mb_load_buddy\n __filemap_get_folio(create|lock)\n folio_lock\n ext4_mb_init_cache\n folio_mark_uptodate\n __filemap_get_folio(no lock)\n ......\n mb_mark_used\n mb_mark_used_double\n mb_cmp_bitmaps\n mb_set_bits(e4b->bd_bitmap)\n folio_unlock\n\nThe original logic assumed that since mb_cmp_bitmaps is called when the\nbitmap is newly loaded from disk, the folio lock would be sufficient to\nprevent concurrent access. However, this overlooks a specific race\ncondition: if another process attempts to load buddy and finds the folio\nis already in an uptodate state, it will immediately begin using it without\nholding folio lock."}], "id": "CVE-2026-45942", "lastModified": "2026-10-30T13:18:53.790", "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-2026-45942", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-10-16T15:18:28.384884Z", "version": "2.0.3"}}]}, "published": "2026-05-27T14:17:10.427", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/29a07d691d282faf38c33d4b61839b89399110f9"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/57e83bfbe1e412ac42daced2086f3c6f9a17bba0"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a3a7d360252c0d84ae8bda067fb296c9e82928d3"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/bdc56a9c46b2a99c12313122b9352b619a2e719e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/c05033cfc5c7699cd4df8d48cef94d01da755f24"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/f29709a7a3fc38f5015d850504762cdef0e151f9"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Undergoing Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-362"}], "source": "nvd@nist.gov", "type": "Primary"}, {"description": [{"lang": "en", "value": "CWE-362"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{"bugzilla": {"description": "kernel: ext4: fix e4b bitmap inconsistency reports", "id": "2482104", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2482104"}, "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"}, "cwe": "CWE-367", "details": ["A flaw was found in the Linux kernel's ext4 filesystem. A race condition exists between page migration and bitmap modification within the `load_buddy` function. This can lead to bitmap inconsistencies and false positive corruption reports during certain workloads. This issue can affect data integrity reporting and system stability."], "name": "CVE-2026-45942", "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": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "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": "2026-05-27T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-45942\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-45942\nhttps://lore.kernel.org/linux-cve-announce/2026052729-CVE-2026-45942-fe56@gregkh/T"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,57e83bfbe1e412ac42daced2086f3c6f9a17bba0)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,c05033cfc5c7699cd4df8d48cef94d01da755f24)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,29a07d691d282faf38c33d4b61839b89399110f9)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,f29709a7a3fc38f5015d850504762cdef0e151f9)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1da177e4c3f41524e886b7f1b8a0c1fc7321cac2,bdc56a9c46b2a99c12313122b9352b619a2e719e)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.6.130)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.12.75)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.18.14)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.19.4)"}}], "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": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.130,6.7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.75,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.14,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.19.4,6.20.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.0,*]"}}], "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": "2026-05-27T19:00:16.896310+00:00", "updated": "2026-08-13T23:15:12.604892+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}