CVE-2026-31589

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-31589", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-03-09T15:48:24.120Z", "datePublished": "2026-04-24T14:42:16.955Z", "dateUpdated": "2026-08-05T12:23:40.286Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:23:40.286Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm: call ->free_folio() directly in folio_unmap_invalidate()\n\nWe can only call filemap_free_folio() if we have a reference to (or hold a\nlock on) the mapping. Otherwise, we've already removed the folio from the\nmapping so it no longer pins the mapping and the mapping can be removed,\ncausing a use-after-free when accessing mapping->a_ops.\n\nFollow the same pattern as __remove_mapping() and load the free_folio\nfunction pointer before dropping the lock on the mapping. That lets us\nmake filemap_free_folio() static as this was the only caller outside\nfilemap.c."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL"}, "scenarios": [{"lang": "en", "value": "AV:N - The vulnerable path can be reached by remote NFS clients when nfsd is configured for NFSD_IO_DONTCACHE on a filesystem advertising FOP_DONTCACHE, causing remote READ/WRITE handling to set IOCB_DONTCACHE and enter the dropbehind invalidation path. This is a network-facing kernel service.\nAC:L - Once the affected DONTCACHE path is available, an attacker can repeatedly drive writeback/dropbehind and inode lifetime pressure with ordinary I/O operations. The race is attacker-influenced rather than dependent on an uncontrollable system state.\nPR:N - A remote NFS client can reach nfsd request processing without local shell access or kernel capabilities on the target; permissive or anonymous exports make the relevant file operations reachable without prior target privileges. When uncertain between N and L, N is the higher-severity defensible choice.\nUI:N - No victim user action is needed after the service and export are available. The attacker triggers the path by sending I/O requests.\nS:U - The vulnerability corrupts/uses freed memory inside the same kernel security authority that processes the request. It is not a VM escape, IOMMU bypass, or cross-authority boundary violation.\nC:H - The bug is a use-after-free of the address_space/inode-backed mapping when dereferencing mapping->a_ops after the folio no longer pins the mapping. Kernel UAFs are defensibly scored as high confidentiality impact because they can be shaped into kernel memory disclosure primitives.\nI:H - The stale mapping dereference includes an indirect free_folio function pointer lookup and potential call, making control-flow or memory corruption exploitation defensible. Kernel UAFs are scored high for integrity under the provided guidance.\nA:H - At minimum, dereferencing mapping->a_ops after the mapping has been freed can crash or oops the kernel. The attacker can trigger the vulnerable path repeatedly, so availability impact is high."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["mm/filemap.c", "mm/internal.h", "mm/truncate.c"], "versions": [{"version": "fb7d3bc4149395c1ae99029c852eab6c28fc3c88", "lessThan": "efc52947247a21bbf79059539bbbd40f4ea76f00", "status": "affected", "versionType": "git"}, {"version": "fb7d3bc4149395c1ae99029c852eab6c28fc3c88", "lessThan": "b667df39d98a7a24be7c2a40ff0863dac1ad2cd7", "status": "affected", "versionType": "git"}, {"version": "fb7d3bc4149395c1ae99029c852eab6c28fc3c88", "lessThan": "c330e65ea59c4805d6ab6757c4ddfe8c63acef31", "status": "affected", "versionType": "git"}, {"version": "fb7d3bc4149395c1ae99029c852eab6c28fc3c88", "lessThan": "615d9bb2ccad42f9e21d837431e401db2e471195", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["mm/filemap.c", "mm/internal.h", "mm/truncate.c"], "versions": [{"version": "6.14", "status": "affected"}, {"version": "0", "lessThan": "6.14", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.27", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.19.14", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.0.1", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1", "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": "6.14", "versionEndExcluding": "6.18.27"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14", "versionEndExcluding": "6.19.14"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14", "versionEndExcluding": "7.0.1"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14", "versionEndExcluding": "7.1"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/efc52947247a21bbf79059539bbbd40f4ea76f00"}, {"url": "https://git.kernel.org/stable/c/b667df39d98a7a24be7c2a40ff0863dac1ad2cd7"}, {"url": "https://git.kernel.org/stable/c/c330e65ea59c4805d6ab6757c4ddfe8c63acef31"}, {"url": "https://git.kernel.org/stable/c/615d9bb2ccad42f9e21d837431e401db2e471195"}], "title": "mm: call ->free_folio() directly in folio_unmap_invalidate()", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["mm/filemap.c", "mm/internal.h", "mm/truncate.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "efc52947247a21bbf79059539bbbd40f4ea76f00", "status": "affected", "version": "fb7d3bc4149395c1ae99029c852eab6c28fc3c88", "versionType": "git"}, {"lessThan": "b667df39d98a7a24be7c2a40ff0863dac1ad2cd7", "status": "affected", "version": "fb7d3bc4149395c1ae99029c852eab6c28fc3c88", "versionType": "git"}, {"lessThan": "c330e65ea59c4805d6ab6757c4ddfe8c63acef31", "status": "affected", "version": "fb7d3bc4149395c1ae99029c852eab6c28fc3c88", "versionType": "git"}, {"lessThan": "615d9bb2ccad42f9e21d837431e401db2e471195", "status": "affected", "version": "fb7d3bc4149395c1ae99029c852eab6c28fc3c88", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["mm/filemap.c", "mm/internal.h", "mm/truncate.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.14"}, {"lessThan": "6.14", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.27", "versionType": "semver"}, {"lessThanOrEqual": "6.19.*", "status": "unaffected", "version": "6.19.14", "versionType": "semver"}, {"lessThanOrEqual": "7.0.*", "status": "unaffected", "version": "7.0.1", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.1", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "24221FC1-03CA-4C3B-99B7-27AFF9FC5FAE", "versionEndExcluding": "6.19.14", "versionStartIncluding": "6.14", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "9B5888AB-7403-4335-89E4-21CC0B48366A", "versionEndExcluding": "7.0.1", "versionStartIncluding": "7.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmm: call ->free_folio() directly in folio_unmap_invalidate()\n\nWe can only call filemap_free_folio() if we have a reference to (or hold a\nlock on) the mapping. Otherwise, we've already removed the folio from the\nmapping so it no longer pins the mapping and the mapping can be removed,\ncausing a use-after-free when accessing mapping->a_ops.\n\nFollow the same pattern as __remove_mapping() and load the free_folio\nfunction pointer before dropping the lock on the mapping. That lets us\nmake filemap_free_folio() static as this was the only caller outside\nfilemap.c."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nmm: llamar a -> free_folio() directamente en folio_unmap_invalidate()\n\nSolo podemos llamar a filemap_free_folio() si tenemos una referencia a (o mantenemos un bloqueo sobre) el mapeo. De lo contrario, ya hemos eliminado el folio del mapeo, por lo que ya no fija el mapeo y el mapeo puede ser eliminado, causando un uso despu\u00e9s de liberaci\u00f3n al acceder a mapping -> a_ops.\n\nSiga el mismo patr\u00f3n que __remove_mapping() y cargue el puntero de funci\u00f3n free_folio antes de liberar el bloqueo sobre el mapeo. Eso nos permite hacer filemap_free_folio() est\u00e1tica, ya que este era el \u00fanico llamador fuera de filemap.c."}], "id": "CVE-2026-31589", "lastModified": "2026-11-11T23:10:00.263", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 9.8, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-04-24T15:16:34.700", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/615d9bb2ccad42f9e21d837431e401db2e471195"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/b667df39d98a7a24be7c2a40ff0863dac1ad2cd7"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/c330e65ea59c4805d6ab6757c4ddfe8c63acef31"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/efc52947247a21bbf79059539bbbd40f4ea76f00"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-416"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: mm: call ->free_folio() directly in folio_unmap_invalidate()", "id": "2461515", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2461515"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.6", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H", "status": "draft"}, "cwe": "CWE-825", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nmm: call ->free_folio() directly in folio_unmap_invalidate()\nWe can only call filemap_free_folio() if we have a reference to (or hold a\nlock on) the mapping. Otherwise, we've already removed the folio from the\nmapping so it no longer pins the mapping and the mapping can be removed,\ncausing a use-after-free when accessing mapping->a_ops.\nFollow the same pattern as __remove_mapping() and load the free_folio\nfunction pointer before dropping the lock on the mapping. That lets us\nmake filemap_free_folio() static as this was the only caller outside\nfilemap.c.", "A flaw was found in the Linux kernel's memory management. This vulnerability, known as a use-after-free, occurs when the system attempts to access a memory region after it has been released. Specifically, during the unmapping and invalidation of a memory page (folio), the system can incorrectly access a freed mapping structure. This can lead to memory corruption, potentially allowing an attacker to cause system instability or execute unauthorized code."], "name": "CVE-2026-31589", "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": "2026-04-24T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-31589\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-31589\nhttps://lore.kernel.org/linux-cve-announce/2026042414-CVE-2026-31589-18ae@gregkh/T"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[fb7d3bc4149395c1ae99029c852eab6c28fc3c88,b667df39d98a7a24be7c2a40ff0863dac1ad2cd7)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[fb7d3bc4149395c1ae99029c852eab6c28fc3c88,c330e65ea59c4805d6ab6757c4ddfe8c63acef31)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[fb7d3bc4149395c1ae99029c852eab6c28fc3c88,615d9bb2ccad42f9e21d837431e401db2e471195)"}}], "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": "generic", "value": "6.14"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.14)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.19.14,6.20.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.0.1,7.1.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1-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"}], "analysis": {"en": {"generated_at": "2026-04-28T23:42:21.655922+00:00", "value": {"mitigation_remediation": ["Apply a kernel update that incorporates the fix for the use\u2011after\u2011free in folio_unmap_invalidate", "Reboot the system to load the updated kernel", "Consider disabling or limiting kernel modules that perform memory mapping operations until a patch is available"], "summary": {"action": "Immediate Patch", "impact": "Use\u2011After\u2011Free leading to kernel memory corruption and possible privilege escalation"}, "threat_synthesis": {"affected_systems": "All current Linux kernel versions are potentially affected until a patched version is installed. The vulnerability is present in the generic Linux kernel, affecting all vendor builds that use the upstream kernel without the patch.", "description_and_impact": "The flaw occurs in the Linux kernel memory manager, where a handler calls the free operation on a folio after the mapping lock has been released. This allows the folio to be freed while the mapping still exists, resulting in a use\u2011after\u2011free of mapping->a_ops. The flaw can lead to code execution in kernel mode, giving an attacker local privilege escalation.", "risk_and_exploitability": "The CVSS score of 9.8 indicates a high severity vulnerability. The EPSS score is less than 1%, suggesting a low probability of exploitation at this time, and the vulnerability is not listed in the CISA KEV catalog. However, because the flaw is a use\u2011after\u2011free in the kernel, an attacker with local access could potentially trigger it by manipulating memory mapping operations, leading to privilege escalation."}}}}, "created": "2026-04-27T19:00:15.671071+00:00", "updated": "2026-04-28T23:45:16.060043+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}