{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-64385", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T15:36:31.784Z", "datePublished": "2026-07-25T08:50:33.997Z", "dateUpdated": "2026-08-17T04:54:37.258Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T04:54:37.258Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: fix double-free in SMB2_ioctl() replay\n\nA response-bearing attempt can return a replayable error and free its\nresponse buffer. If SMB2_ioctl_init() fails before the next send, cleanup\nretains the previous buffer type and frees that response again.\n\nReset response bookkeeping before each attempt to prevent the stale free." } ], "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 - An attacker-controlled SMB server can deliver crafted SMB2 IOCTL responses over TCP, including through the kernel's periodic interface-query FSCTL on an existing SMB3 mount.\nAC:L - On a hard or retrans-enabled mount, the server controls replayable statuses, response contents, disconnects, reconnects, and repeated attempts, allowing it to drive both sides of the triggering sequence.\nPR:N - The malicious SMB server needs no account or privilege on the target; victim mounting authority and client authentication do not grant or require attacker-side target privileges.\nUI:N - Once the share is mounted, kernel delayed work can automatically issue the affected FSCTL when the server advertises multichannel support, requiring no user action during exploitation.\nS:U - The memory corruption compromises resources governed by the same host-kernel security authority and does not inherently cross a VM, container, or IOMMU boundary.\nC:H - The response-buffer double-free can corrupt SLUB or mempool state and create dangling or overlapping live buffers, enabling use-after-free exploitation and kernel-memory disclosure.\nI:H - Attacker-controlled network data can overwrite aliased or freed buffers and poison allocator state, supporting arbitrary writes and control-flow hijacking.\nA:H - The duplicate free can trigger an allocator BUG or corrupt kernel heap state, causing an oops, panic, or complete system crash." } ] } ], "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": "0be4bc64882edaefaaee8d1e27d083643eb778e6", "status": "affected", "versionType": "git" }, { "version": "4f1fffa2376922f3d1d506e49c0fd445b023a28e", "lessThan": "96fcfc8ae7359346156e492ca610e830d2649ad6", "status": "affected", "versionType": "git" }, { "version": "4f1fffa2376922f3d1d506e49c0fd445b023a28e", "lessThan": "276c8efbc49f9303ac76d0d4deab7128581b0f3b", "status": "affected", "versionType": "git" }, { "version": "4f1fffa2376922f3d1d506e49c0fd445b023a28e", "lessThan": "fc65ffb4ef1bf540da16b17c225ae51091e07d72", "status": "affected", "versionType": "git" }, { "version": "4f1fffa2376922f3d1d506e49c0fd445b023a28e", "lessThan": "f9bbadb6c94583e3b4af1afc449bfceb1d1ddec9", "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", "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" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/0be4bc64882edaefaaee8d1e27d083643eb778e6" }, { "url": "https://git.kernel.org/stable/c/96fcfc8ae7359346156e492ca610e830d2649ad6" }, { "url": "https://git.kernel.org/stable/c/276c8efbc49f9303ac76d0d4deab7128581b0f3b" }, { "url": "https://git.kernel.org/stable/c/fc65ffb4ef1bf540da16b17c225ae51091e07d72" }, { "url": "https://git.kernel.org/stable/c/f9bbadb6c94583e3b4af1afc449bfceb1d1ddec9" } ], "title": "smb: client: fix double-free in SMB2_ioctl() replay", "x_generator": { "engine": "bippy-1.2.0" } } } }