{"api_version":"1","generated_at":"2026-05-08T19:31:56+00:00","cve":"CVE-2026-43185","urls":{"html":"https://cve.report/CVE-2026-43185","api":"https://cve.report/api/cve/CVE-2026-43185.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-43185","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-43185"},"summary":{"title":"ksmbd: fix signededness bug in smb_direct_prepare_negotiation()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix signededness bug in smb_direct_prepare_negotiation()\n\nsmb_direct_prepare_negotiation() casts an unsigned __u32 value\nfrom sp->max_recv_size and req->preferred_send_size to a signed\nint before computing min_t(int, ...). A maliciously provided\npreferred_send_size of 0x80000000 will return as smaller than\nmax_recv_size, and then be used to set the maximum allowed\nalowed receive size for the next message.\n\nBy sending a second message with a large value (>1420 bytes)\nthe attacker can then achieve a heap buffer overflow.\n\nThis fix replaces min_t(int, ...) with min_t(u32)","state":"PUBLISHED","assigner":"Linux","published_at":"2026-05-06 12:16:37","updated_at":"2026-05-08 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the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix signededness bug in smb_direct_prepare_negotiation()\n\nsmb_direct_prepare_negotiation() casts an unsigned __u32 value\nfrom sp->max_recv_size and req->preferred_send_size to a signed\nint before computing min_t(int, ...). A maliciously provided\npreferred_send_size of 0x80000000 will return as smaller than\nmax_recv_size, and then be used to set the maximum allowed\nalowed receive size for the next message.\n\nBy sending a second message with a large value (>1420 bytes)\nthe attacker can then achieve a heap buffer overflow.\n\nThis fix replaces min_t(int, ...) with min_t(u32)"}],"metrics":[{"cvssV3_1":{"baseScore":9.8,"baseSeverity":"CRITICAL","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"providerMetadata":{"dateUpdated":"2026-05-08T12:41:03.371Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/ceae058eb707ddd0d68f0872f9d9f23b7c30c37b"},{"url":"https://git.kernel.org/stable/c/55abc475d096da4a5356b6efb0cfdc6156bc1550"},{"url":"https://git.kernel.org/stable/c/6b4f875aac344cdd52a1f34cc70ed2f874a65757"}],"title":"ksmbd: fix signededness bug in smb_direct_prepare_negotiation()","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-43185","datePublished":"2026-05-06T11:27:56.386Z","dateReserved":"2026-05-01T14:12:55.991Z","dateUpdated":"2026-05-08T12:41:03.371Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-05-06 12:16:37","lastModifiedDate":"2026-05-08 13:16:42","problem_types":[],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"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","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":5.9}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"43185","Ordinal":"1","Title":"ksmbd: fix signededness bug in smb_direct_prepare_negotiation()","CVE":"CVE-2026-43185","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"43185","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix signededness bug in smb_direct_prepare_negotiation()\n\nsmb_direct_prepare_negotiation() casts an unsigned __u32 value\nfrom sp->max_recv_size and req->preferred_send_size to a signed\nint before computing min_t(int, ...). A maliciously provided\npreferred_send_size of 0x80000000 will return as smaller than\nmax_recv_size, and then be used to set the maximum allowed\nalowed receive size for the next message.\n\nBy sending a second message with a large value (>1420 bytes)\nthe attacker can then achieve a heap buffer overflow.\n\nThis fix replaces min_t(int, ...) with min_t(u32)","Type":"Description","Title":"ksmbd: fix signededness bug in smb_direct_prepare_negotiation()"}]}}}