{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-64383", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T15:36:31.784Z", "datePublished": "2026-07-25T08:50:32.634Z", "dateUpdated": "2026-08-05T12:41:18.383Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:41:18.383Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: fix double-free in SMB2_flush() replay\n\nSMB2_flush() keeps its response buffer bookkeeping across replay\nattempts. If a replayable flush response is received and the retry then\nfails before cifs_send_recv() stores a replacement response, flush_exit\nwill free the stale response pointer a second time.\n\nReinitialize resp_buftype and rsp_iov at the top of the replay loop so\ncleanup only acts on response state produced by the current attempt.\nThis fixes a double-free without changing replay handling for successful\nrequests."}], "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 - A malicious or compromised SMB server can trigger the flaw through crafted replayable responses and connection failures over the network.\nAC:L - The server controls both the replayable error and subsequent reconnect failure, allowing repeated triggering without an uncontrollable race.\nPR:N - The attacking SMB endpoint requires no privileges on the client system once an SMB session and file handle exist.\nUI:N - An automatically mounted share and routine service-generated fsync, truncate, timestamp, or seek operations can reach SMB2_flush() without human participation.\nS:U - The memory corruption compromises resources governed by the same host kernel security authority.\nC:H - The response-buffer double-free can create overlapping CIFS slab allocations and use-after-free primitives capable of exposing arbitrary kernel memory.\nI:H - Allocator corruption and attacker-influenced overlapping network buffers can provide arbitrary-write or control-flow-hijacking primitives.\nA:H - The double-free can immediately trigger an allocator BUG, kernel oops, or panic and can be invoked repeatedly."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/smb/client/smb2pdu.c"], "versions": [{"version": "433042a91f9373241307725b52de573933ffedbf", "lessThan": "6e27f40b682a5e42a2daae3ce6d96f0e0e16dedb", "status": "affected", "versionType": "git"}, {"version": "4f1fffa2376922f3d1d506e49c0fd445b023a28e", "lessThan": "878757163eea684750107a31ea134c103863515d", "status": "affected", "versionType": "git"}, {"version": "4f1fffa2376922f3d1d506e49c0fd445b023a28e", "lessThan": "3407240cde132a4b72d6429a2625a09a2f78adaf", "status": "affected", "versionType": "git"}, {"version": "4f1fffa2376922f3d1d506e49c0fd445b023a28e", "lessThan": "013a9a3da46c5dabcf18f65ea6a47874ba12a15d", "status": "affected", "versionType": "git"}, {"version": "4f1fffa2376922f3d1d506e49c0fd445b023a28e", "lessThan": "4be31c943a3a27a5a0251dbb8f5cb89059ec3d5a", "status": "affected", "versionType": "git"}, {"version": "6.6.32", "lessThan": "6.6.145", "status": "affected", "versionType": "semver"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/smb/client/smb2pdu.c"], "versions": [{"version": "6.8", "status": "affected"}, {"version": "0", "lessThan": "6.8", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.145", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.96", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.39", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.4", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2-rc1", "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": "6.6.32", "versionEndExcluding": "6.6.145"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.8", "versionEndExcluding": "6.12.96"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.8", "versionEndExcluding": "6.18.39"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.8", "versionEndExcluding": "7.1.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.8", "versionEndExcluding": "7.2-rc1"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/6e27f40b682a5e42a2daae3ce6d96f0e0e16dedb"}, {"url": "https://git.kernel.org/stable/c/878757163eea684750107a31ea134c103863515d"}, {"url": "https://git.kernel.org/stable/c/3407240cde132a4b72d6429a2625a09a2f78adaf"}, {"url": "https://git.kernel.org/stable/c/013a9a3da46c5dabcf18f65ea6a47874ba12a15d"}, {"url": "https://git.kernel.org/stable/c/4be31c943a3a27a5a0251dbb8f5cb89059ec3d5a"}], "title": "smb: client: fix double-free in SMB2_flush() replay", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/smb/client/smb2pdu.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "6e27f40b682a5e42a2daae3ce6d96f0e0e16dedb", "status": "affected", "version": "433042a91f9373241307725b52de573933ffedbf", "versionType": "git"}, {"lessThan": "878757163eea684750107a31ea134c103863515d", "status": "affected", "version": "4f1fffa2376922f3d1d506e49c0fd445b023a28e", "versionType": "git"}, {"lessThan": "3407240cde132a4b72d6429a2625a09a2f78adaf", "status": "affected", "version": "4f1fffa2376922f3d1d506e49c0fd445b023a28e", "versionType": "git"}, {"lessThan": "013a9a3da46c5dabcf18f65ea6a47874ba12a15d", "status": "affected", "version": "4f1fffa2376922f3d1d506e49c0fd445b023a28e", "versionType": "git"}, {"lessThan": "4be31c943a3a27a5a0251dbb8f5cb89059ec3d5a", "status": "affected", "version": "4f1fffa2376922f3d1d506e49c0fd445b023a28e", "versionType": "git"}, {"lessThan": "6.6.145", "status": "affected", "version": "6.6.32", "versionType": "semver"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/smb/client/smb2pdu.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "6.8"}, {"lessThan": "6.8", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.145", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.96", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.39", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.4", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.2-rc1", "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\nsmb: client: fix double-free in SMB2_flush() replay\n\nSMB2_flush() keeps its response buffer bookkeeping across replay\nattempts. If a replayable flush response is received and the retry then\nfails before cifs_send_recv() stores a replacement response, flush_exit\nwill free the stale response pointer a second time.\n\nReinitialize resp_buftype and rsp_iov at the top of the replay loop so\ncleanup only acts on response state produced by the current attempt.\nThis fixes a double-free without changing replay handling for successful\nrequests."}], "id": "CVE-2026-64383", "lastModified": "2026-08-11T15:01:50.637", "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": "2026-07-25T10:17:21.587", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/013a9a3da46c5dabcf18f65ea6a47874ba12a15d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/3407240cde132a4b72d6429a2625a09a2f78adaf"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/4be31c943a3a27a5a0251dbb8f5cb89059ec3d5a"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/6e27f40b682a5e42a2daae3ce6d96f0e0e16dedb"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/878757163eea684750107a31ea134c103863515d"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Awaiting Analysis"}

{"bugzilla": {"description": "kernel: smb: client: fix double-free in SMB2_flush() replay", "id": "2507134", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2507134"}, "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": ["A flaw was found in the Linux kernel's Server Message Block (SMB) client. This vulnerability, a double-free error within the `SMB2_flush()` replay mechanism, occurs when the system attempts to free a memory buffer twice. A malicious SMB server could exploit this by sending a specially crafted flush response, potentially leading to memory corruption. This could result in a denial of service or, in some scenarios, arbitrary code execution."], "name": "CVE-2026-64383", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "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": "2026-07-25T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-64383\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-64383\nhttps://lore.kernel.org/linux-cve-announce/2026072525-CVE-2026-64383-5a13@gregkh/T"], "threat_severity": "Important"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[433042a91f9373241307725b52de573933ffedbf,6e27f40b682a5e42a2daae3ce6d96f0e0e16dedb)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4f1fffa2376922f3d1d506e49c0fd445b023a28e,878757163eea684750107a31ea134c103863515d)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4f1fffa2376922f3d1d506e49c0fd445b023a28e,3407240cde132a4b72d6429a2625a09a2f78adaf)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4f1fffa2376922f3d1d506e49c0fd445b023a28e,013a9a3da46c5dabcf18f65ea6a47874ba12a15d)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4f1fffa2376922f3d1d506e49c0fd445b023a28e,4be31c943a3a27a5a0251dbb8f5cb89059ec3d5a)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[6.6.32,6.6.145)"}}], "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": "6.8"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,6.8)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.145,6.7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.96,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.39,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1.4,7.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.2-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"}], "created": "2026-07-25T16:00:05.059687+00:00", "updated": "2026-08-04T14:45:03.285795+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-416"]}