CVE-2026-31446

{"id": "CVE-2026-31446", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-31446", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2026-10-16T15:09:20.883316Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.8, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 1.8}]}, "affected": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "affectedData": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "52c3a04f9ec2a16a4204d6274db338cb8d5b2d74", "lessThan": "c8fe17a1b308c3d8c703ebfb049b325f844342c3", "versionType": "git"}, {"status": "affected", "version": "b98535d091795a79336f520b0708457aacf55c67", "lessThan": "c4d829737329f2290dd41e290b7d75effdb2a7ff", "versionType": "git"}, {"status": "affected", "version": "b98535d091795a79336f520b0708457aacf55c67", "lessThan": "9449f99ba04f5dd1c8423ad8a90b3651d7240d1d", "versionType": "git"}, {"status": "affected", "version": "b98535d091795a79336f520b0708457aacf55c67", "lessThan": "034053378dd81837fd6c7a43b37ee2e58d4f0b4e", "versionType": "git"}, {"status": "affected", "version": "b98535d091795a79336f520b0708457aacf55c67", "lessThan": "c97e282f7bfd0c3554c63d289964a5ca6a1d2ffe", "versionType": "git"}, {"status": "affected", "version": "b98535d091795a79336f520b0708457aacf55c67", "lessThan": "08b10e6f37fc533a759e9833af0692242e8b3f93", "versionType": "git"}, {"status": "affected", "version": "b98535d091795a79336f520b0708457aacf55c67", "lessThan": "d15e4b0a418537aafa56b2cb80d44add83e83697", "versionType": "git"}, {"status": "affected", "version": "585ef03c9e79672781f954daae730dfe24bf3a46", "versionType": "git"}, {"status": "affected", "version": "afe490e48d47df1b3f64012835c1bc2f075a8c8b", "versionType": "git"}, {"status": "affected", "version": "5.15.38", "lessThan": "5.15.203", "versionType": "semver"}, {"status": "affected", "version": "5.10.114", "lessThan": "5.11", "versionType": "semver"}, {"status": "affected", "version": "5.17.6", "lessThan": "5.18", "versionType": "semver"}], "programFiles": ["fs/ext4/ext4.h", "fs/ext4/super.c", "fs/ext4/sysfs.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "5.18"}, {"status": "unaffected", "version": "0", "lessThan": "5.18", "versionType": "semver"}, {"status": "unaffected", "version": "5.15.203", "versionType": "semver", "lessThanOrEqual": "5.15.*"}, {"status": "unaffected", "version": "6.1.168", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.131", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.80", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.21", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "6.19.11", "versionType": "semver", "lessThanOrEqual": "6.19.*"}, {"status": "unaffected", "version": "7.0", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["fs/ext4/ext4.h", "fs/ext4/super.c", "fs/ext4/sysfs.c"], "defaultStatus": "affected"}]}, {"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "affectedData": [{"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)", "versions": [{"status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)", "versions": [{"status": "affected", "version": "V3.1.5", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0)", "versions": [{"status": "affected", "version": "V3.1.7", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0)", "versions": [{"status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0)", "versions": [{"status": "affected", "version": "V3.1.5", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0)", "versions": [{"status": "affected", "version": "V3.1.7", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)", "versions": [{"status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)", "versions": [{"status": "affected", "version": "V3.1.5", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0)", "versions": [{"status": "affected", "version": "V3.1.7", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)", "versions": [{"status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)", "versions": [{"status": "affected", "version": "V3.1.5", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0)", "versions": [{"status": "affected", "version": "V3.1.7", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)", "versions": [{"status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)", "versions": [{"status": "affected", "version": "V3.1.5", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}, {"vendor": "Siemens", "product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0)", "versions": [{"status": "affected", "version": "V3.1.7", "lessThan": "*", "versionType": "custom"}], "defaultStatus": "unknown"}]}], "published": "2026-04-22T14:16:38.340", "references": [{"url": "https://git.kernel.org/stable/c/034053378dd81837fd6c7a43b37ee2e58d4f0b4e", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/08b10e6f37fc533a759e9833af0692242e8b3f93", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/9449f99ba04f5dd1c8423ad8a90b3651d7240d1d", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/c4d829737329f2290dd41e290b7d75effdb2a7ff", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/c8fe17a1b308c3d8c703ebfb049b325f844342c3", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/c97e282f7bfd0c3554c63d289964a5ca6a1d2ffe", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/d15e4b0a418537aafa56b2cb80d44add83e83697", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html", "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}, {"url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html", "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}, {"url": "https://cert-portal.siemens.com/productcert/html/ssa-457936.html", "source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-416"}]}, {"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-416"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix use-after-free in update_super_work when racing with umount\n\nCommit b98535d09179 (\"ext4: fix bug_on in start_this_handle during umount\nfilesystem\") moved ext4_unregister_sysfs() before flushing s_sb_upd_work\nto prevent new error work from being queued via /proc/fs/ext4/xx/mb_groups\nreads during unmount. However, this introduced a use-after-free because\nupdate_super_work calls ext4_notify_error_sysfs() -> sysfs_notify() which\naccesses the kobject's kernfs_node after it has been freed by kobject_del()\nin ext4_unregister_sysfs():\n\n update_super_work ext4_put_super\n ----------------- --------------\n ext4_unregister_sysfs(sb)\n kobject_del(&sbi->s_kobj)\n __kobject_del()\n sysfs_remove_dir()\n kobj->sd = NULL\n sysfs_put(sd)\n kernfs_put() // RCU free\n ext4_notify_error_sysfs(sbi)\n sysfs_notify(&sbi->s_kobj)\n kn = kobj->sd // stale pointer\n kernfs_get(kn) // UAF on freed kernfs_node\n ext4_journal_destroy()\n flush_work(&sbi->s_sb_upd_work)\n\nInstead of reordering the teardown sequence, fix this by making\next4_notify_error_sysfs() detect that sysfs has already been torn down\nby checking s_kobj.state_in_sysfs, and skipping the sysfs_notify() call\nin that case. A dedicated mutex (s_error_notify_mutex) serializes\next4_notify_error_sysfs() against kobject_del() in ext4_unregister_sysfs()\nto prevent TOCTOU races where the kobject could be deleted between the\nstate_in_sysfs check and the sysfs_notify() call."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\next4: corrige el uso despu\u00e9s de liberaci\u00f3n en update_super_work cuando compite con umount\n\nEl commit b98535d09179 (\u2019ext4: corrige bug_on en start_this_handle durante el desmontaje del sistema de archivos\u2019) movi\u00f3 ext4_unregister_sysfs() antes de vaciar s_sb_upd_work para evitar que se encole nuevo trabajo de error a trav\u00e9s de lecturas de /proc/fs/ext4/xx/mb_groups durante el desmontaje. Sin embargo, esto introdujo un uso despu\u00e9s de liberaci\u00f3n porque update_super_work llama a ext4_notify_error_sysfs() -> sysfs_notify() que accede al kernfs_node del kobject despu\u00e9s de que ha sido liberado por kobject_del() en ext4_unregister_sysfs():\n\n update_super_work ext4_put_super\n - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -\n ext4_unregister_sysfs(sb)\n kobject_del(ref:sbi -> s_kobj)\n __kobject_del()\n sysfs_remove_dir()\n kobj -> sd = NULL\n sysfs_put(sd)\n kernfs_put() // liberaci\u00f3n RCU\n ext4_notify_error_sysfs(sbi)\n sysfs_notify(ref:sbi -> s_kobj)\n kn = kobj -> sd // puntero obsoleto\n kernfs_get(kn) // UAF en kernfs_node liberado\n ext4_journal_destroy()\n flush_work(ref:sbi -> s_sb_upd_work)\n\nEn lugar de reordenar la secuencia de desmontaje, corrige esto haciendo que ext4_notify_error_sysfs() detecte que sysfs ya ha sido desmontado verificando s_kobj.state_in_sysfs, y omitiendo la llamada a sysfs_notify() en ese caso. Un mutex dedicado (s_error_notify_mutex) serializa ext4_notify_error_sysfs() frente a kobject_del() en ext4_unregister_sysfs() para prevenir condiciones de carrera TOCTOU donde el kobject podr\u00eda ser eliminado entre la verificaci\u00f3n de state_in_sysfs y la llamada a sysfs_notify()."}], "lastModified": "2026-11-11T23:10:00.263", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "06D67EC3-92E2-452F-9826-4CF918434F2B", "versionEndExcluding": "5.11", "versionStartIncluding": "5.10.114"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "237A1663-E334-49A1-A031-5A8D1A1782AD", "versionEndExcluding": "5.15.203", "versionStartIncluding": "5.15.38"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "49134C93-AD6F-411A-A4B1-E5E509EEFB00", "versionEndExcluding": "5.18", "versionStartIncluding": "5.17.6"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0292DDCD-3BB0-457C-AB09-7796072CC1DB", "versionEndExcluding": "6.1.168", "versionStartIncluding": "5.18.1"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "CE6ED4D4-0046-4573-BFA9-D64143B6A89F", "versionEndExcluding": "6.6.131", "versionStartIncluding": "6.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "97EB19EC-A11E-49C6-9D2F-6F6EC6CB98B6", "versionEndExcluding": "6.12.80", "versionStartIncluding": "6.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "ED39847A-3B46-4729-B7CA-B2C30B9FA8FE", "versionEndExcluding": "6.18.21", "versionStartIncluding": "6.13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4CA2E747-A9EC-4518-9AA2-B4247FC748B7", "versionEndExcluding": "6.19.11", "versionStartIncluding": "6.19"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.18:-:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0384FA0A-DE99-48D7-84E3-46ED0C3B5E03"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.18:rc4:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "DA5F085D-52F3-4EE2-8353-455D1A6FE073"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.18:rc5:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D6EE5B78-0D83-4715-893C-ABD69B49E7FC"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.18:rc6:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "EE723F14-047B-4FCF-B109-E0542EDFB063"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.18:rc7:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "2FCFCE58-5118-4D05-864E-C82CF20EABE5"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.18:rc9:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "9C3E5BC9-613C-4362-BF02-153A5BBFFB2F"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}