{"api_version":"1","generated_at":"2026-09-26T20:44:23+00:00","cve":"CVE-2026-97937","urls":{"html":"https://cve.report/CVE-2026-97937","api":"https://cve.report/api/cve/CVE-2026-97937.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-97937","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-97937"},"summary":{"title":"ftrace: fork: Initialize function graph state before copy_exec_state()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nftrace: fork: Initialize function graph state before copy_exec_state()\n\ndup_task_struct() copies the parent's task_struct, including ret_stack.\nftrace_graph_init_task() clears the copied function graph state, but it\ncurrently runs after copy_exec_state().\n\nFor non-CLONE_VM forks, copy_exec_state() allocates a new task_exec_state.\nIf that allocation fails, copy_process() reaches bad_fork_free and\nfree_task() calls ftrace_graph_exit_task(). Since the child still carries\nthe parent's ret_stack pointer, the unwind frees the parent's active\nfunction graph return stack. The parent subsequently accesses freed memory\nfrom function_graph_enter_regs().\n\nKASAN reports:\n\n[   22.190920] ==================================================================\n[   22.195899] BUG: KASAN: slab-use-after-free in function_graph_enter_regs+0xa76/0xb90\n[   22.200747] Write of size 8 at addr ff110000054dc0a8 by task repro/1\n[   22.205134]\n[   22.210770] CPU: 0 UID: 0 PID: 1 Comm: repro Not tainted 7.2.0-07732-g9328b3b03bdc-dirty #3 PREEMPT(lazy)\n[   22.212576] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n[   22.213750] Call Trace:\n[   22.215271]  <TASK>\n[   22.216242]  ? ftrace_stub_direct_tramp+0x10/0x10\n[   22.217774]  dump_stack_lvl+0x4e/0x70\n[   22.220531]  print_report+0x157/0x4b4\n[   22.223202]  ? fixup_red_left+0x9/0x30\n[   22.224407]  ? complete_report_info+0x83/0x110\n[   22.226679]  ? function_graph_enter_regs+0xa76/0xb90\n[   22.228084]  kasan_report+0xce/0x100\n[   22.230109]  ? function_graph_enter_regs+0xa76/0xb90\n[   22.232860]  ? stack_trace_save+0x4/0xd0\n[   22.234156]  function_graph_enter_regs+0xa76/0xb90\n[   22.236090]  ? kasan_save_stack+0x30/0x50\n[   22.237752]  ? __pfx_function_graph_enter_regs+0x10/0x10\n[   22.238694]  ? ring_buffer_lock_reserve+0x345/0xf80\n[   22.239628]  ? stack_trace_save+0x4/0xd0\n[   22.242121]  ? stack_trace_save+0x4/0xd0\n[   22.243588]  ftrace_graph_func+0xda/0x160\n[   22.245362]  ? ftrace_stub_direct_tramp+0x10/0x10\n[   22.246520]  0xffffffffa0000095\n[   22.250528]  ? stack_trace_save+0x9/0xd0\n[   22.251757]  ? ring_buffer_unlock_commit+0x11d/0x5c0\n[   22.253152]  stack_trace_save+0x9/0xd0\n[   22.254264]  kasan_save_stack+0x30/0x50\n[   22.273631]  kasan_save_track+0x14/0x30\n[   22.276763]  kasan_save_free_info+0x3b/0x70\n[   22.278296]  __kasan_slab_free+0x43/0x70\n[   22.280157]  kmem_cache_free+0xbf/0x3b0\n[   22.282963]  ? ftrace_stub_direct_tramp+0x10/0x10\n[   22.284001]  free_task+0xa2/0x160\n[   22.285699]  ? ftrace_stub_direct_tramp+0x10/0x10\n[   22.286752]  copy_process+0x2aae/0x7bc0\n\nInitialize the child function graph state immediately after\ndup_task_struct(), before the first fallible operation.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-25 11:17:21","updated_at":"2026-09-25 15:18:02"},"problem_types":[],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"7.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"7.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"baseScore":7.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/08cacffeef8f64f1a222c93467ca84f24a46c953","name":"https://git.kernel.org/stable/c/08cacffeef8f64f1a222c93467ca84f24a46c953","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/1fadebbbf31f65beba353fa9d1373bf183e03fed","name":"https://git.kernel.org/stable/c/1fadebbbf31f65beba353fa9d1373bf183e03fed","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-97937","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-97937","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6b1c66c9cca99bf00386481c7b2aa7394c26d8b8 1fadebbbf31f65beba353fa9d1373bf183e03fed git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6b1c66c9cca99bf00386481c7b2aa7394c26d8b8 08cacffeef8f64f1a222c93467ca84f24a46c953 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7.2","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.7 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc3 * 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":["kernel/fork.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"1fadebbbf31f65beba353fa9d1373bf183e03fed","status":"affected","version":"6b1c66c9cca99bf00386481c7b2aa7394c26d8b8","versionType":"git"},{"lessThan":"08cacffeef8f64f1a222c93467ca84f24a46c953","status":"affected","version":"6b1c66c9cca99bf00386481c7b2aa7394c26d8b8","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["kernel/fork.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"7.2"},{"lessThan":"7.2","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.7","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc3","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.7","versionStartIncluding":"7.2","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc3","versionStartIncluding":"7.2","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nftrace: fork: Initialize function graph state before copy_exec_state()\n\ndup_task_struct() copies the parent's task_struct, including ret_stack.\nftrace_graph_init_task() clears the copied function graph state, but it\ncurrently runs after copy_exec_state().\n\nFor non-CLONE_VM forks, copy_exec_state() allocates a new task_exec_state.\nIf that allocation fails, copy_process() reaches bad_fork_free and\nfree_task() calls ftrace_graph_exit_task(). Since the child still carries\nthe parent's ret_stack pointer, the unwind frees the parent's active\nfunction graph return stack. The parent subsequently accesses freed memory\nfrom function_graph_enter_regs().\n\nKASAN reports:\n\n[   22.190920] ==================================================================\n[   22.195899] BUG: KASAN: slab-use-after-free in function_graph_enter_regs+0xa76/0xb90\n[   22.200747] Write of size 8 at addr ff110000054dc0a8 by task repro/1\n[   22.205134]\n[   22.210770] CPU: 0 UID: 0 PID: 1 Comm: repro Not tainted 7.2.0-07732-g9328b3b03bdc-dirty #3 PREEMPT(lazy)\n[   22.212576] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n[   22.213750] Call Trace:\n[   22.215271]  <TASK>\n[   22.216242]  ? ftrace_stub_direct_tramp+0x10/0x10\n[   22.217774]  dump_stack_lvl+0x4e/0x70\n[   22.220531]  print_report+0x157/0x4b4\n[   22.223202]  ? fixup_red_left+0x9/0x30\n[   22.224407]  ? complete_report_info+0x83/0x110\n[   22.226679]  ? function_graph_enter_regs+0xa76/0xb90\n[   22.228084]  kasan_report+0xce/0x100\n[   22.230109]  ? function_graph_enter_regs+0xa76/0xb90\n[   22.232860]  ? stack_trace_save+0x4/0xd0\n[   22.234156]  function_graph_enter_regs+0xa76/0xb90\n[   22.236090]  ? kasan_save_stack+0x30/0x50\n[   22.237752]  ? __pfx_function_graph_enter_regs+0x10/0x10\n[   22.238694]  ? ring_buffer_lock_reserve+0x345/0xf80\n[   22.239628]  ? stack_trace_save+0x4/0xd0\n[   22.242121]  ? stack_trace_save+0x4/0xd0\n[   22.243588]  ftrace_graph_func+0xda/0x160\n[   22.245362]  ? ftrace_stub_direct_tramp+0x10/0x10\n[   22.246520]  0xffffffffa0000095\n[   22.250528]  ? stack_trace_save+0x9/0xd0\n[   22.251757]  ? ring_buffer_unlock_commit+0x11d/0x5c0\n[   22.253152]  stack_trace_save+0x9/0xd0\n[   22.254264]  kasan_save_stack+0x30/0x50\n[   22.273631]  kasan_save_track+0x14/0x30\n[   22.276763]  kasan_save_free_info+0x3b/0x70\n[   22.278296]  __kasan_slab_free+0x43/0x70\n[   22.280157]  kmem_cache_free+0xbf/0x3b0\n[   22.282963]  ? ftrace_stub_direct_tramp+0x10/0x10\n[   22.284001]  free_task+0xa2/0x160\n[   22.285699]  ? ftrace_stub_direct_tramp+0x10/0x10\n[   22.286752]  copy_process+0x2aae/0x7bc0\n\nInitialize the child function graph state immediately after\ndup_task_struct(), before the first fallible operation."}],"metrics":[{"cvssV3_1":{"baseScore":7.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"scenarios":[{"lang":"en","value":"AV:L - Triggered by a local fork()/clone() without CLONE_VM entering copy_process(): copy_exec_state() -> task_exec_state_copy() fails, and bad_fork_free -> free_task() -> ftrace_graph_exit_task() frees the ret_stack pointer the child inherited from the parent. No remote input is involved.\nAC:L - placeholder\nPR:L - placeholder\nUI:N - placeholder\nS:U - placeholder\nC:H - placeholder\nI:H - placeholder\nA:H - placeholder"}]}],"providerMetadata":{"dateUpdated":"2026-09-25T14:41:40.998Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/1fadebbbf31f65beba353fa9d1373bf183e03fed"},{"url":"https://git.kernel.org/stable/c/08cacffeef8f64f1a222c93467ca84f24a46c953"}],"title":"ftrace: fork: Initialize function graph state before copy_exec_state()","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-97937","datePublished":"2026-09-25T10:22:51.075Z","dateReserved":"2026-09-25T10:18:58.204Z","dateUpdated":"2026-09-25T14:41:40.998Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-25 11:17:21","lastModifiedDate":"2026-09-25 15:18:02","problem_types":[],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":5.9}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"97937","Ordinal":"1","Title":"ftrace: fork: Initialize function graph state before copy_exec_s","CVE":"CVE-2026-97937","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"97937","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nftrace: fork: Initialize function graph state before copy_exec_state()\n\ndup_task_struct() copies the parent's task_struct, including ret_stack.\nftrace_graph_init_task() clears the copied function graph state, but it\ncurrently runs after copy_exec_state().\n\nFor non-CLONE_VM forks, copy_exec_state() allocates a new task_exec_state.\nIf that allocation fails, copy_process() reaches bad_fork_free and\nfree_task() calls ftrace_graph_exit_task(). Since the child still carries\nthe parent's ret_stack pointer, the unwind frees the parent's active\nfunction graph return stack. The parent subsequently accesses freed memory\nfrom function_graph_enter_regs().\n\nKASAN reports:\n\n[   22.190920] ==================================================================\n[   22.195899] BUG: KASAN: slab-use-after-free in function_graph_enter_regs+0xa76/0xb90\n[   22.200747] Write of size 8 at addr ff110000054dc0a8 by task repro/1\n[   22.205134]\n[   22.210770] CPU: 0 UID: 0 PID: 1 Comm: repro Not tainted 7.2.0-07732-g9328b3b03bdc-dirty #3 PREEMPT(lazy)\n[   22.212576] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\n[   22.213750] Call Trace:\n[   22.215271]  <TASK>\n[   22.216242]  ? ftrace_stub_direct_tramp+0x10/0x10\n[   22.217774]  dump_stack_lvl+0x4e/0x70\n[   22.220531]  print_report+0x157/0x4b4\n[   22.223202]  ? fixup_red_left+0x9/0x30\n[   22.224407]  ? complete_report_info+0x83/0x110\n[   22.226679]  ? function_graph_enter_regs+0xa76/0xb90\n[   22.228084]  kasan_report+0xce/0x100\n[   22.230109]  ? function_graph_enter_regs+0xa76/0xb90\n[   22.232860]  ? stack_trace_save+0x4/0xd0\n[   22.234156]  function_graph_enter_regs+0xa76/0xb90\n[   22.236090]  ? kasan_save_stack+0x30/0x50\n[   22.237752]  ? __pfx_function_graph_enter_regs+0x10/0x10\n[   22.238694]  ? ring_buffer_lock_reserve+0x345/0xf80\n[   22.239628]  ? stack_trace_save+0x4/0xd0\n[   22.242121]  ? stack_trace_save+0x4/0xd0\n[   22.243588]  ftrace_graph_func+0xda/0x160\n[   22.245362]  ? ftrace_stub_direct_tramp+0x10/0x10\n[   22.246520]  0xffffffffa0000095\n[   22.250528]  ? stack_trace_save+0x9/0xd0\n[   22.251757]  ? ring_buffer_unlock_commit+0x11d/0x5c0\n[   22.253152]  stack_trace_save+0x9/0xd0\n[   22.254264]  kasan_save_stack+0x30/0x50\n[   22.273631]  kasan_save_track+0x14/0x30\n[   22.276763]  kasan_save_free_info+0x3b/0x70\n[   22.278296]  __kasan_slab_free+0x43/0x70\n[   22.280157]  kmem_cache_free+0xbf/0x3b0\n[   22.282963]  ? ftrace_stub_direct_tramp+0x10/0x10\n[   22.284001]  free_task+0xa2/0x160\n[   22.285699]  ? ftrace_stub_direct_tramp+0x10/0x10\n[   22.286752]  copy_process+0x2aae/0x7bc0\n\nInitialize the child function graph state immediately after\ndup_task_struct(), before the first fallible operation.","Type":"Description","Title":"ftrace: fork: Initialize function graph state before copy_exec_s"}]}}}