{"api_version":"1","generated_at":"2026-07-20T14:43:25+00:00","cve":"CVE-2026-64140","urls":{"html":"https://cve.report/CVE-2026-64140","api":"https://cve.report/api/cve/CVE-2026-64140.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-64140","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-64140"},"summary":{"title":"ksmbd: fix null pointer dereference in proc_show_files()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix null pointer dereference in proc_show_files()\n\nWhen a SMB2 client opens a file with a durable v2 handle and then issues\nSMB2 SESSION_LOGOFF, session_fd_check() clears fp->tcon = NULL on the\nreconnectable file pointer but leaves the fp registered in global_ft.idr\nuntil the durable scavenger fires (up to fp->durable_timeout seconds\nlater).\n\nDuring that window any read of /proc/fs/ksmbd/files (mode 0400) panics\nthe kernel because proc_show_files() walks global_ft.idr and\nunconditionally dereferences fp->tcon->id with no NULL guard.\n\nReproducer requires only a successful SMB2 SESSION_SETUP and a share\nconfigured with 'durable handles = yes'. KASAN report on mainline\n70390501d194:\n\n  general protection fault, probably for non-canonical address\n  0xdffffc0000000000: 0000 [#1] SMP KASAN PTI\n  KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]\n  RIP: 0010:proc_show_files+0x118/0x740\n  Call Trace:\n   proc_show_files+0x118/0x740\n   seq_read_iter+0x4ef/0xe10\n   proc_reg_read_iter+0x1b7/0x280\n   ...\n\nGuard the dereference. A durable-disconnected fp legitimately has no\ntcon; report its tree id as 0 rather than oopsing.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-07-19 16:17:55","updated_at":"2026-07-19 16:17:55"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/904901561e61a2b559070b20c74a8c95491f30aa","name":"https://git.kernel.org/stable/c/904901561e61a2b559070b20c74a8c95491f30aa","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/8eab081627b67216d1c8f638b68289b500dc9a6b","name":"https://git.kernel.org/stable/c/8eab081627b67216d1c8f638b68289b500dc9a6b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-64140","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64140","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b38f99c1217ae04753340f0fdcd8f35bf56841dc 8eab081627b67216d1c8f638b68289b500dc9a6b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b38f99c1217ae04753340f0fdcd8f35bf56841dc 904901561e61a2b559070b20c74a8c95491f30aa git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7.0","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0.11 7.0.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["fs/smb/server/vfs_cache.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"8eab081627b67216d1c8f638b68289b500dc9a6b","status":"affected","version":"b38f99c1217ae04753340f0fdcd8f35bf56841dc","versionType":"git"},{"lessThan":"904901561e61a2b559070b20c74a8c95491f30aa","status":"affected","version":"b38f99c1217ae04753340f0fdcd8f35bf56841dc","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["fs/smb/server/vfs_cache.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":"7.0.*","status":"unaffected","version":"7.0.11","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0.11","versionStartIncluding":"7.0","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1","versionStartIncluding":"7.0","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix null pointer dereference in proc_show_files()\n\nWhen a SMB2 client opens a file with a durable v2 handle and then issues\nSMB2 SESSION_LOGOFF, session_fd_check() clears fp->tcon = NULL on the\nreconnectable file pointer but leaves the fp registered in global_ft.idr\nuntil the durable scavenger fires (up to fp->durable_timeout seconds\nlater).\n\nDuring that window any read of /proc/fs/ksmbd/files (mode 0400) panics\nthe kernel because proc_show_files() walks global_ft.idr and\nunconditionally dereferences fp->tcon->id with no NULL guard.\n\nReproducer requires only a successful SMB2 SESSION_SETUP and a share\nconfigured with 'durable handles = yes'. KASAN report on mainline\n70390501d194:\n\n  general protection fault, probably for non-canonical address\n  0xdffffc0000000000: 0000 [#1] SMP KASAN PTI\n  KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]\n  RIP: 0010:proc_show_files+0x118/0x740\n  Call Trace:\n   proc_show_files+0x118/0x740\n   seq_read_iter+0x4ef/0xe10\n   proc_reg_read_iter+0x1b7/0x280\n   ...\n\nGuard the dereference. A durable-disconnected fp legitimately has no\ntcon; report its tree id as 0 rather than oopsing."}],"providerMetadata":{"dateUpdated":"2026-07-19T15:40:33.194Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/8eab081627b67216d1c8f638b68289b500dc9a6b"},{"url":"https://git.kernel.org/stable/c/904901561e61a2b559070b20c74a8c95491f30aa"}],"title":"ksmbd: fix null pointer dereference in proc_show_files()","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-64140","datePublished":"2026-07-19T15:40:33.194Z","dateReserved":"2026-07-19T07:54:57.037Z","dateUpdated":"2026-07-19T15:40:33.194Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-07-19 16:17:55","lastModifiedDate":"2026-07-19 16:17:55","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"64140","Ordinal":"1","Title":"ksmbd: fix null pointer dereference in proc_show_files()","CVE":"CVE-2026-64140","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"64140","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix null pointer dereference in proc_show_files()\n\nWhen a SMB2 client opens a file with a durable v2 handle and then issues\nSMB2 SESSION_LOGOFF, session_fd_check() clears fp->tcon = NULL on the\nreconnectable file pointer but leaves the fp registered in global_ft.idr\nuntil the durable scavenger fires (up to fp->durable_timeout seconds\nlater).\n\nDuring that window any read of /proc/fs/ksmbd/files (mode 0400) panics\nthe kernel because proc_show_files() walks global_ft.idr and\nunconditionally dereferences fp->tcon->id with no NULL guard.\n\nReproducer requires only a successful SMB2 SESSION_SETUP and a share\nconfigured with 'durable handles = yes'. KASAN report on mainline\n70390501d194:\n\n  general protection fault, probably for non-canonical address\n  0xdffffc0000000000: 0000 [#1] SMP KASAN PTI\n  KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]\n  RIP: 0010:proc_show_files+0x118/0x740\n  Call Trace:\n   proc_show_files+0x118/0x740\n   seq_read_iter+0x4ef/0xe10\n   proc_reg_read_iter+0x1b7/0x280\n   ...\n\nGuard the dereference. A durable-disconnected fp legitimately has no\ntcon; report its tree id as 0 rather than oopsing.","Type":"Description","Title":"ksmbd: fix null pointer dereference in proc_show_files()"}]}}}