CVE-2026-31608

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-31608", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-03-09T15:48:24.122Z", "datePublished": "2026-04-24T14:42:30.137Z", "dateUpdated": "2026-08-05T12:23:46.955Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:23:46.955Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: server: avoid double-free in smb_direct_free_sendmsg after smb_direct_flush_send_list()\n\nsmb_direct_flush_send_list() already calls smb_direct_free_sendmsg(),\nso we should not call it again after post_sendmsg()\nmoved it to the batch list."}], "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 - SMB Direct in ksmbd is exposed over RDMA network listeners on SMB-related ports, and a remote RDMA-capable peer can reach the vulnerable send path. The affected subsystem is an in-kernel SMB server transport, so the defensible vector is Network.\nAC:L - The attacker can establish an SMB Direct connection, request immediate/credit responses, and induce send failure by controlling the peer connection state. Any timing involved is attacker-controlled and repeatable, so complexity is Low.\nPR:N - The vulnerable path is reachable after RDMA/SMB Direct transport negotiation and before SMB user authentication. No valid SMB session or credentials are required to trigger the lower transport credit/keepalive send path.\nUI:N - Exploitation only requires network interaction with the listening ksmbd SMB Direct service. No victim user action is needed.\nS:U - The corruption occurs within the kernel handling the ksmbd transport and impacts the same kernel security authority. This is not a VM escape, sandbox boundary crossing, or separate security scope.\nC:H - The bug is a kernel heap double-free of an SMB Direct send object, which can create use-after-free or overlapping-allocation conditions. Such memory corruption can reasonably be leveraged for kernel memory disclosure, so Confidentiality is High.\nI:H - A double-free in kernel heap/mempool state can be exploitable for controlled memory corruption and potentially control-flow or data modification. Following the higher-severity rule for memory corruption, Integrity is High.\nA:H - At minimum, the double-free can corrupt allocator state or trigger kernel warnings/oops/panic during send teardown. A remote unauthenticated peer can repeatedly trigger the condition, so Availability is High."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/smb/server/transport_rdma.c"], "versions": [{"version": "5ef18a2e66f2f33fdac64437bddfb9fe6389fdc7", "lessThan": "6968c91fab05b8fc4d6700e0cf34472bb422df25", "status": "affected", "versionType": "git"}, {"version": "79242e7b6bc63efec28b7c235bc320806afce6c0", "lessThan": "2ba03f46132b0d1a7bafb86e1ef61951a2254023", "status": "affected", "versionType": "git"}, {"version": "34abd408c8ba24d7c97bd02ba874d8c714f49db1", "lessThan": "830de6eeb9db4cb7e758201fb99328ef4ca4b032", "status": "affected", "versionType": "git"}, {"version": "34abd408c8ba24d7c97bd02ba874d8c714f49db1", "lessThan": "84ff995ae826aa6bbcc6c7b9ea569ff67c021d72", "status": "affected", "versionType": "git"}, {"version": "6.18.11", "lessThan": "6.18.24", "status": "affected", "versionType": "semver"}, {"version": "6.19.1", "lessThan": "6.19.14", "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/server/transport_rdma.c"], "versions": [{"version": "7.0", "status": "affected"}, {"version": "0", "lessThan": "7.0", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.24", "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": "6.18.11", "versionEndExcluding": "6.18.24"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19.1", "versionEndExcluding": "6.19.14"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.0", "versionEndExcluding": "7.0.1"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "7.0", "versionEndExcluding": "7.1"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/6968c91fab05b8fc4d6700e0cf34472bb422df25"}, {"url": "https://git.kernel.org/stable/c/2ba03f46132b0d1a7bafb86e1ef61951a2254023"}, {"url": "https://git.kernel.org/stable/c/830de6eeb9db4cb7e758201fb99328ef4ca4b032"}, {"url": "https://git.kernel.org/stable/c/84ff995ae826aa6bbcc6c7b9ea569ff67c021d72"}], "title": "smb: server: avoid double-free in smb_direct_free_sendmsg after smb_direct_flush_send_list()", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/smb/server/transport_rdma.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "6968c91fab05b8fc4d6700e0cf34472bb422df25", "status": "affected", "version": "5ef18a2e66f2f33fdac64437bddfb9fe6389fdc7", "versionType": "git"}, {"lessThan": "2ba03f46132b0d1a7bafb86e1ef61951a2254023", "status": "affected", "version": "79242e7b6bc63efec28b7c235bc320806afce6c0", "versionType": "git"}, {"lessThan": "830de6eeb9db4cb7e758201fb99328ef4ca4b032", "status": "affected", "version": "34abd408c8ba24d7c97bd02ba874d8c714f49db1", "versionType": "git"}, {"lessThan": "84ff995ae826aa6bbcc6c7b9ea569ff67c021d72", "status": "affected", "version": "34abd408c8ba24d7c97bd02ba874d8c714f49db1", "versionType": "git"}, {"lessThan": "6.18.24", "status": "affected", "version": "6.18.11", "versionType": "semver"}, {"lessThan": "6.19.14", "status": "affected", "version": "6.19.1", "versionType": "semver"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/smb/server/transport_rdma.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "7.0"}, {"lessThan": "7.0", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.24", "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": "E7BFA239-2F39-4B24-92AA-6F60AA187C18", "versionEndExcluding": "6.18.24", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "D6A8A074-BBF4-4803-ABED-519A839435BB", "versionEndExcluding": "6.19.14", "versionStartIncluding": "6.19", "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\nsmb: server: avoid double-free in smb_direct_free_sendmsg after smb_direct_flush_send_list()\n\nsmb_direct_flush_send_list() already calls smb_direct_free_sendmsg(),\nso we should not call it again after post_sendmsg()\nmoved it to the batch list."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nsmb: servidor: evitar doble liberaci\u00f3n en smb_direct_free_sendmsg despu\u00e9s de smb_direct_flush_send_list()\n\nsmb_direct_flush_send_list() ya llama a smb_direct_free_sendmsg(),\npor lo que no deber\u00edamos llamarla de nuevo despu\u00e9s de que post_sendmsg() la moviera a la lista de lotes."}], "id": "CVE-2026-31608", "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": "2026-04-24T15:16:40.063", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/2ba03f46132b0d1a7bafb86e1ef61951a2254023"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/6968c91fab05b8fc4d6700e0cf34472bb422df25"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/830de6eeb9db4cb7e758201fb99328ef4ca4b032"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/84ff995ae826aa6bbcc6c7b9ea569ff67c021d72"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-415"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: smb: server: avoid double-free in smb_direct_free_sendmsg after smb_direct_flush_send_list()", "id": "2461452", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2461452"}, "csaw": false, "cwe": "CWE-1341", "details": ["A flaw was found in the Linux kernel's Server Message Block (SMB) server component. This vulnerability, a double-free error, occurs when the `smb_direct_free_sendmsg` function is called redundantly after `smb_direct_flush_send_list()` has already executed it. A remote attacker could potentially exploit this flaw, leading to memory corruption and a denial of service (DoS) on the affected system."], "name": "CVE-2026-31608", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "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": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not 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-2026-31608\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-31608\nhttps://lore.kernel.org/linux-cve-announce/2026042421-CVE-2026-31608-1786@gregkh/T"]}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5ef18a2e66f2f33fdac64437bddfb9fe6389fdc7,6968c91fab05b8fc4d6700e0cf34472bb422df25)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[79242e7b6bc63efec28b7c235bc320806afce6c0,2ba03f46132b0d1a7bafb86e1ef61951a2254023)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[34abd408c8ba24d7c97bd02ba874d8c714f49db1,830de6eeb9db4cb7e758201fb99328ef4ca4b032)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[34abd408c8ba24d7c97bd02ba874d8c714f49db1,84ff995ae826aa6bbcc6c7b9ea569ff67c021d72)"}}], "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": "7.0"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.24,6.19.0)"}}, {"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"}], "created": "2026-04-27T19:00:15.601616+00:00", "updated": "2026-04-30T14:15:40.618841+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}