CVE-2026-64016

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-64016", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T07:54:57.027Z", "datePublished": "2026-07-19T15:39:11.266Z", "dateUpdated": "2026-09-14T11:58:34.345Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-09-14T11:58:34.345Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix durable reconnect error path file lifetime\n\nAfter a durable reconnect succeeds, ksmbd_reopen_durable_fd() republishes\nthe same ksmbd_file into the session volatile-id table. If smb2_open()\nthen takes a later error path, cleanup first calls ksmbd_fd_put(work, fp)\nand then unconditionally calls ksmbd_put_durable_fd(dh_info.fp).\n\nIn this case fp and dh_info.fp are the same object. The first put drops the\nreconnect lookup reference, but the final durable put can run\n__ksmbd_close_fd(NULL, fp). Because the final close is not session-aware,\nit can free the file object without removing the volatile-id entry that was\njust published into the session table.\n\nUse the session-aware put for the final reconnect drop when the reconnect\nhad already succeeded and the error path is cleaning up the republished\nfile. Earlier reconnect failures, before fp is assigned to dh_info.fp, keep\nusing the durable-only put path."}], "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 vulnerability is reached through ksmbd's in-kernel SMB2 server on TCP port 445 via SMB2_CREATE durable-handle reconnect processing in smb2_open(), reachable by any remote SMB client that can connect to the server.\nAC:L - An authenticated attacker can fully control the durable reconnect sequence (open with durable handle, disconnect to preserve it, reconnect, then force a post-reconnect error such as ksmbd_iov_pin_rsp() ENOMEM) and immediately exercise the stale volatile file ID via further SMB2 operations.\nPR:N - Exploitation requires only network reachability to ksmbd and valid SMB session credentials (guest or any share user); no elevated kernel privileges, capabilities, or local access are needed beyond what any remote SMB client possesses.\nUI:N - No victim user interaction is required beyond the server running ksmbd with durable handles enabled; the attacker drives the entire reconnect-and-error sequence over the network.\nS:U - The use-after-free corrupts kernel heap memory within the ksmbd server context and can lead to privilege escalation on the host, but does not cross a VM, container, or IOMMU security boundary.\nC:H - Freeing the ksmbd_file while its volatile ID remains in the session IDR creates a use-after-free; subsequent ksmbd_lookup_fd_slow() dereferences freed slab memory, enabling kernel information disclosure.\nI:H - The UAF corrupts kernel heap objects (struct ksmbd_file in the filp kmem cache) and can be leveraged with heap grooming for arbitrary kernel memory writes or code execution.\nA:H - Use-after-free of the ksmbd_file object can cause kernel oopses or panics when freed memory is reused or dereferenced during subsequent SMB2 file operations on the stale volatile ID."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/smb/server/smb2pdu.c"], "versions": [{"version": "f0ff7f12398e85b3a11745ff7feab6246f3d75c2", "lessThan": "5e641e4ee0bc1937408d41051a908ad4151be63b", "status": "affected", "versionType": "git"}, {"version": "4db3dcac84c2f14a45ae201efb38de1fb1bfc009", "lessThan": "478bfaa036bd0c7e179acff8b8484bccdee3b8c7", "status": "affected", "versionType": "git"}, {"version": "ce2e164c1c51c3f7813b80f8c926836e896bcbb3", "lessThan": "a1a39f227c80cbf369767badc32cba2b225147d1", "status": "affected", "versionType": "git"}, {"version": "97a0cd55283b4e63fd92804da91c8d9896adcad9", "lessThan": "6cb0b9385320110fe24a5d5ac0000ade4bb3a3f3", "status": "affected", "versionType": "git"}, {"version": "1baff47b81f94f9231c91236aa511420d0e266b9", "lessThan": "3515503322f4819277091839eed46b695096aca5", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/smb/server/smb2pdu.c"], "versions": [{"version": "6.18.33", "lessThan": "6.18.34", "status": "affected", "versionType": "semver"}, {"version": "7.0.10", "lessThan": "7.0.11", "status": "affected", "versionType": "semver"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.18.33", "versionEndExcluding": "6.18.34"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.0.10", "versionEndExcluding": "7.0.11"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/5e641e4ee0bc1937408d41051a908ad4151be63b"}, {"url": "https://git.kernel.org/stable/c/478bfaa036bd0c7e179acff8b8484bccdee3b8c7"}, {"url": "https://git.kernel.org/stable/c/a1a39f227c80cbf369767badc32cba2b225147d1"}, {"url": "https://git.kernel.org/stable/c/6cb0b9385320110fe24a5d5ac0000ade4bb3a3f3"}, {"url": "https://git.kernel.org/stable/c/3515503322f4819277091839eed46b695096aca5"}], "title": "ksmbd: fix durable reconnect error path file lifetime", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/smb/server/smb2pdu.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "5e641e4ee0bc1937408d41051a908ad4151be63b", "status": "affected", "version": "f0ff7f12398e85b3a11745ff7feab6246f3d75c2", "versionType": "git"}, {"lessThan": "478bfaa036bd0c7e179acff8b8484bccdee3b8c7", "status": "affected", "version": "4db3dcac84c2f14a45ae201efb38de1fb1bfc009", "versionType": "git"}, {"lessThan": "a1a39f227c80cbf369767badc32cba2b225147d1", "status": "affected", "version": "ce2e164c1c51c3f7813b80f8c926836e896bcbb3", "versionType": "git"}, {"lessThan": "6cb0b9385320110fe24a5d5ac0000ade4bb3a3f3", "status": "affected", "version": "97a0cd55283b4e63fd92804da91c8d9896adcad9", "versionType": "git"}, {"lessThan": "3515503322f4819277091839eed46b695096aca5", "status": "affected", "version": "1baff47b81f94f9231c91236aa511420d0e266b9", "versionType": "git"}]}, {"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/smb/server/smb2pdu.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "6.18.34", "status": "affected", "version": "6.18.33", "versionType": "semver"}, {"lessThan": "7.0.11", "status": "affected", "version": "7.0.10", "versionType": "semver"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:6.18.33:*:*:*:*:*:*:*", "matchCriteriaId": "1D121C8A-7E04-48D9-9107-20F776371EF4", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.0.10:*:*:*:*:*:*:*", "matchCriteriaId": "8B9C50B1-4501-41E5-B0EA-6A66F3B343AE", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*", "matchCriteriaId": "B1EF7059-E670-45F4-B422-54C40FA86390", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*", "matchCriteriaId": "0D38F0BF-A728-4133-A358-D44A2F7EE6D6", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*", "matchCriteriaId": "EC732D08-5F7B-46D9-B154-E60C7F4F0A97", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*", "matchCriteriaId": "E5910A9D-F60A-409A-B486-FE66BFEBA9B9", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix durable reconnect error path file lifetime\n\nAfter a durable reconnect succeeds, ksmbd_reopen_durable_fd() republishes\nthe same ksmbd_file into the session volatile-id table. If smb2_open()\nthen takes a later error path, cleanup first calls ksmbd_fd_put(work, fp)\nand then unconditionally calls ksmbd_put_durable_fd(dh_info.fp).\n\nIn this case fp and dh_info.fp are the same object. The first put drops the\nreconnect lookup reference, but the final durable put can run\n__ksmbd_close_fd(NULL, fp). Because the final close is not session-aware,\nit can free the file object without removing the volatile-id entry that was\njust published into the session table.\n\nUse the session-aware put for the final reconnect drop when the reconnect\nhad already succeeded and the error path is cleaning up the republished\nfile. Earlier reconnect failures, before fp is assigned to dh_info.fp, keep\nusing the durable-only put path."}], "id": "CVE-2026-64016", "lastModified": "2026-10-13T14:48:12.317", "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": "2026-07-19T16:17:41.577", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/3515503322f4819277091839eed46b695096aca5"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/478bfaa036bd0c7e179acff8b8484bccdee3b8c7"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/5e641e4ee0bc1937408d41051a908ad4151be63b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/6cb0b9385320110fe24a5d5ac0000ade4bb3a3f3"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/a1a39f227c80cbf369767badc32cba2b225147d1"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-416"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: ksmbd: fix durable reconnect error path file lifetime", "id": "2502315", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2502315"}, "csaw": false, "cwe": "CWE-825", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nksmbd: fix durable reconnect error path file lifetime\nAfter a durable reconnect succeeds, ksmbd_reopen_durable_fd() republishes\nthe same ksmbd_file into the session volatile-id table. If smb2_open()\nthen takes a later error path, cleanup first calls ksmbd_fd_put(work, fp)\nand then unconditionally calls ksmbd_put_durable_fd(dh_info.fp).\nIn this case fp and dh_info.fp are the same object. The first put drops the\nreconnect lookup reference, but the final durable put can run\n__ksmbd_close_fd(NULL, fp). Because the final close is not session-aware,\nit can free the file object without removing the volatile-id entry that was\njust published into the session table.\nUse the session-aware put for the final reconnect drop when the reconnect\nhad already succeeded and the error path is cleaning up the republished\nfile. Earlier reconnect failures, before fp is assigned to dh_info.fp, keep\nusing the durable-only put path.", "A flaw was found in the Linux kernel's ksmbd component, which handles file sharing. When a durable network connection is re-established, an error in managing the lifetime of file objects can occur. This can lead to a situation where a file object is released from memory while still being referenced, creating a use-after-free vulnerability. An attacker could potentially exploit this to cause the system to crash (denial of service) or, in more severe cases, execute unauthorized code."], "name": "CVE-2026-64016", "package_state": [{"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Not affected", "impact": "important", "package_name": "erlang27", "product_name": "Red Hat Hardened Images"}], "public_date": "2026-07-19T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-64016\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-64016\nhttps://lore.kernel.org/linux-cve-announce/2026071900-CVE-2026-64016-577b@gregkh/T"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[ce2e164c1c51c3f7813b80f8c926836e896bcbb3,a1a39f227c80cbf369767badc32cba2b225147d1)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[97a0cd55283b4e63fd92804da91c8d9896adcad9,6cb0b9385320110fe24a5d5ac0000ade4bb3a3f3)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[1baff47b81f94f9231c91236aa511420d0e266b9,3515503322f4819277091839eed46b695096aca5)"}}], "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": "semver", "value": "[6.18.33,6.18.34)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[7.0.10,7.0.11)"}}], "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": "2026-07-21T07:30:03.261243+00:00", "updated": "2026-10-17T11:00:07.375123+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}